Every television series begins with a promise.

Give us your time. Your attention. Your imagination. Follow these characters wherever their story takes them, and return each week to see what happens next.

In return, we'll tell you a story. And when it's over, we'll bring it to its proper end. We'll answer the questions, settle the conflicts, and give the characters—and the audience—a chance to say goodbye.

Most series keep that promise. Some don't.

And some broke it so long ago that their unfinished stories have been gathering dust for decades.

Heroes were left lost in time. Families remained stranded on distant worlds. Fugitives kept running. Invaders were never defeated. Quests begun in black and white—or in the first years of color television—simply stopped when the network turned out the lights.

The evidence is old now. The videotapes are fading. The film cans are rusting. The witnesses have scattered. But the questions remain.

Some endings have been missing for a very long time.

These are the Cold Cases.

PART ONE: THE MEN WHO NEVER CAME HOME

Somewhere beneath the Arizona desert, the United States government has spent billions of dollars building a machine that can punch a hole through time.

Project Tic-Toc is one of the most expensive secrets in the country, housed in an enormous underground complex and staffed by scientists who have accomplished something extraordinary. They can look into the past. They can even send someone there.

What they cannot reliably do is bring him back.

That becomes a problem when Senator Leroy Clark arrives to evaluate the project and threatens to cut off its funding unless its scientists can demonstrate that the Time Tunnel actually works. Dr. Tony Newman, one of the men who helped build it, decides that waiting for permission is no longer an option. He steps into the Tunnel himself.

The machine works. On September 9, 1966, ABC viewers watched Tony Newman disappear from 1968 and materialize aboard an ocean liner in 1912. It doesn't take him long to discover which one: the RMS Titanic.

Tony knows exactly what is going to happen. He tries to warn the captain. Nobody believes him. Back at Project Tic-Toc, Tony's colleagues can see what has happened but cannot retrieve him. His friend and fellow scientist Dr. Doug Phillips finally does the only thing he can think of.

He goes in after him. Now Project Tic-Toc has two men lost in time.

That is the engine behind Irwin Allen's THE TIME TUNNEL, but it is also something more important for our purposes: a promise.

Tony Newman and Doug Phillips are not tourists. They haven't volunteered to wander through history indefinitely. They are stranded, involuntarily thrown from one historical period to another while the scientists back home struggle to locate them, communicate with them and—most importantly—bring them back to 1968.

Each week might bring a new setting and a new crisis, but beneath all of those adventures is the same unfinished piece of business.

Get Tony and Doug home. They survive the Titanic. They survive everything that comes afterward. Project Tic-Toc keeps finding them. The Tunnel keeps moving them. But it never brings them home.

ABC aired 30 episodes of THE TIME TUNNEL between September 1966 and April 1967. Then the network shut the project down for good.

Project Tic-Toc lost contact with Tony Newman and Doug Phillips nearly six decades ago.

It's time we found out what happened to them.

PART TWO: THIRTY TRIPS THROUGH HISTORY

THE TIME TUNNEL had a formula, but it was an extraordinarily flexible one.

Tony Newman and Doug Phillips could be dropped almost anywhere, because the premise required little more than a date and a disaster. One week they might find themselves aboard the Titanic. Another could put them at Pearl Harbor, the Alamo or the Battle of Little Bighorn. They crossed paths with historical figures, landed in the middle of wars and revolutions, encountered pirates and conquerors, and occasionally wandered beyond recorded history altogether.

The Time Tunnel could turn virtually any chapter in a history book into next week's television adventure.

It could also cheat.

Although the series initially leaned heavily on recognizable historical events, it increasingly ventured into science fiction, fantasy and outright temporal lunacy. Tony and Doug encountered aliens. They traveled into the future. They dealt with ghosts and ancient legends. They even found themselves caught up in the destruction of Jericho.

Historical accuracy was never going to stand much of a chance against an Irwin Allen television series.

What kept the whole thing connected was Project Tic-Toc.

Back in 1968, Dr. Ann MacGregor, General Heywood Kirk, Dr. Raymond Swain and the rest of the project's personnel watched Tony and Doug through the Tunnel. Sometimes they could communicate with them. Sometimes they could send objects through. Occasionally they could manipulate events just enough to keep the two travelers alive.

And repeatedly, they tried to retrieve them. That's important.

THE TIME TUNNEL certainly became an episodic adventure series. A viewer could miss several episodes and return without needing an elaborate explanation of what had happened in between. Tony and Doug generally arrived somewhere, discovered when and where they were, became entangled in whatever catastrophe history had waiting for them, survived it, and were whisked away to another time.

But the original problem never disappeared. They were still stranded.

The scientists at Project Tic-Toc were still trying to recover them. Tony and Doug still wanted to return to their own time. The weekly adventures didn't replace the underlying objective; they postponed it.

That distinction is what gets THE TIME TUNNEL admitted into the Cold Cases evidence room.

A series such as KOLCHAK: THE NIGHT STALKER could simply stop making episodes. Carl Kolchak didn't have an ultimate destination he was supposed to reach. There was always another monster, another investigation and another editor refusing to believe him. Cancellation ended the series, but it didn't prevent Kolchak from accomplishing some central mission promised by the premise.

Tony and Doug had one: get home. Thirty episodes gave Project Tic-Toc thirty opportunities to accomplish it. They never did.

There is also something wonderfully cruel about the way THE TIME TUNNEL maintained that hope. Tony and Doug weren't simply lost beyond anyone's reach. Their colleagues could often SEE them. The giant temporal screen inside Project Tic-Toc could locate the men somewhere in history, close enough that the scientists knew they were alive and frequently knew exactly what danger they were facing.

Imagine being able to see two missing men on the other side of a window but never being able to open the door.

That was the recurring frustration built into the series.

And because the Time Tunnel could transfer Tony and Doug from one period to another, every successful transfer carried the tantalizing possibility that this time the scientists might finally get the coordinates right.

Instead: Titanic. Ancient Troy. Pearl Harbor. The Alamo. The French Revolution. Krakatoa.

Another century. Another catastrophe. Another near miss.

For viewers in 1966 and 1967, there was always next week. Eventually, however, there wasn't.

After thirty journeys through history, THE TIME TUNNEL didn't reach the end of Tony and Doug's story.

It simply ran out of television.

PART THREE: THE CASE OF THE MISSING SECOND SEASON

THE TIME TUNNEL did not end because Tony and Doug finally made it home. It did not end because Irwin Allen had reached the conclusion of the story he wanted to tell. It ended because ABC changed its mind.

That distinction matters in a Cold Case.

By February 1967, the trade press was already calling another season of THE TIME TUNNEL “questionable.” Yet the story did not end there. James Darren and Robert Colbert later recalled that the cast and crew were told the series had been picked up for a second season. Colbert remembered a huge renewal party on the Time Tunnel soundstage. Darren remembered Allen personally calling him with the good news—and then calling again after the decision had been reversed.

Television historian Martin Grams found evidence of what that second season might have contained. More than 30 story proposals were prepared, and at least one completed first-season teleplay, “Lost Civilization,” appears to have been held over as a possible second-season premiere. Darren was even associated with a proposed Jack the Ripper story.

So this was not merely a case of fans imagining a phantom Season Two decades later. There really was development work for more THE TIME TUNNEL.

What remains murkier is exactly why ABC reversed itself. Later accounts blame a change in network management, the desire to make room for the Western CUSTER, ratings, costs, or some combination of those factors. Contemporary trade reporting confirms that the show's future was uncertain before the season ended; later cast recollections confirm that a renewal was announced internally and then withdrawn. What the surviving evidence does not give us is one clean memo identifying a single culprit.

This wasn't unusual television behavior in 1967. Series were expected to keep producing adventures until the network stopped ordering them. There was no modern assumption that an endangered show should devote its last hour to wrapping up its mythology just in case.

THE TIME TUNNEL was particularly vulnerable to that system. Its format could continue indefinitely. Its premise could not.

The premise still required, someday, an answer to the question posed by the first episode: Can Project Tic-Toc bring Tony and Doug home?

The proposed second-season material tells us something important. Had ABC followed through on the renewal, Tony and Doug were not about to retire from time travel. The surviving pitches send them to lost civilizations, Atlantis, a future Ice Age and still more catastrophes. The machine was going to keep running.

What we do not have is evidence of a planned final episode in which the Tunnel finally brings them home.

Cold Cases require that distinction. A plan for more adventures is not the same thing as a plan for an ending.

And the most important piece of evidence remains the last adventure ABC actually broadcast: Episode 30.

It is called “Town of Terror.” It does not bring them home.

PART FOUR: “TOWN OF TERROR”

If you came to “Town of Terror” expecting THE TIME TUNNEL to start tying up loose ends, the first few minutes would have cured you of that optimism.

Tony and Doug arrive in what appears to be an ordinary American town. It is September 10, 1978—ten years in their future—and something is very wrong.

The streets are deserted. The buildings appear abandoned. There are no people anywhere. Then they discover that the town is not abandoned at all. It has been taken over by aliens.

“Town of Terror,” broadcast April 7, 1967, is the thirtieth and final episode of THE TIME TUNNEL. Nothing about it announces that fact. There is no return to Project Tic-Toc, no final breakthrough in the retrieval problem, no indication that Tony and Doug's long journey is approaching its destination.

It is simply another adventure.

The aliens have evacuated the town's human population and are using the community as a base for an operation that could devastate Earth. Tony and Doug stumble into the plot, are captured, escape, interfere with the invasion and once again become the only people standing between civilization and whatever disaster happened to be waiting for them that week.

Back at Project Tic-Toc, the scientists discover something especially alarming. The aliens know about the Time Tunnel. Worse, they have technology capable of interfering with it.

That should sound like the beginning of something.

An extraterrestrial enemy with knowledge of Project Tic-Toc potentially opens an entirely new avenue for the series. The Tunnel is no longer merely a secret machine whose operators are watching history. Someone outside the project understands what it can do and poses a direct threat to it.

But there is no next chapter. Tony and Doug thwart the immediate danger. The aliens' plan fails. The town's population can be restored. And then the familiar thing happens: the Tunnel takes Tony and Doug away. Not home. Away.

There is no final conversation between the travelers. Tony doesn't look at Doug and wonder how long they can keep doing this. Nobody at Project Tic-Toc promises that the next retrieval attempt will be different. There is no farewell to Ann MacGregor, Ray Swain or General Kirk.

Most tellingly, there is no moment in which the series behaves as though it understands that this is goodbye.

Because it wasn't supposed to be. “Town of Terror” isn't an unsuccessful series finale. It isn't a series finale at all.

It was Episode 30 of a television program whose basic machinery was still running. Tony and Doug survive another crisis. Project Tic-Toc loses another opportunity to retrieve them. The travelers are propelled toward another destination.

Under ordinary circumstances, ABC viewers would have discovered that destination by tuning in again.

And here is where the evidence becomes peculiar.

THE TIME TUNNEL had a familiar way of keeping viewers on the hook. At the end of an episode, Tony and Doug would be thrown into their next predicament, giving the audience a glimpse of the adventure waiting the following week.

At the end of “Town of Terror,” viewers instead see something they have seen before: Tony and Doug are headed for the Titanic, the ship where the whole thing began.

Over the decades, that image has sometimes been treated as though THE TIME TUNNEL deliberately ended by trapping its heroes in an eternal loop: after thirty episodes, Tony and Doug circle all the way back to their first adventure and begin their journey again.

It's a wonderfully eerie ending. There's only one problem: it wasn't the ending.

What viewers were seeing was the machinery of episodic television adapting to the fact that ABC had run out of new episodes. The series was moving into repeats, and the next adventure being promoted was the beginning of the cycle again.

That distinction is essential to this case.

THE TIME TUNNEL did not reveal that Tony and Doug were condemned to repeat their adventures forever. It simply began repeating THE TIME TUNNEL.

For viewers, however, the effect was almost cruelly perfect.

Tony Newman entered the Tunnel and landed aboard the Titanic. Doug Phillips followed him. Thirty episodes later, after surviving wars, disasters, invasions and centuries of human history, the television audience looked into the Tunnel one last time. And there was the Titanic again.

Not because Tony and Doug's journey had come full circle, but because their journey hadn't come to an end at all.

PART FIVE: BACK WHERE THEY STARTED

For decades, THE TIME TUNNEL has carried around one of those television legends that is almost too perfect to question: Tony and Doug begin the series aboard the Titanic, and after thirty episodes the audience sees the Titanic again. Therefore, the theory goes, the two travelers are trapped in an eternal loop, condemned to relive their adventures over and over again.

Seen without the original broadcast context, the effect can look astonishingly deliberate. The series appears to have constructed a perfect circle. Was the Tunnel always going to send them back? Have Tony and Doug already experienced these events countless times? Is that why Project Tic-Toc can never retrieve them? You can build an entire mythology out of those final seconds.

But doing so would require us to manufacture evidence that isn't there. THE TIME TUNNEL routinely ended one adventure by showing the beginning of the next. After “Town of Terror,” there was no Episode 31 for ABC to preview. What the network did have was Episode 1 as the series moved into repeats.

The Titanic footage therefore was not Irwin Allen unveiling the secret of the Time Tunnel. It was television scheduling. The reruns were starting.

That may be less satisfying as science fiction, but it makes the actual fate of Tony and Doug considerably more interesting for a Cold Case. Once we remove the comforting idea of a deliberate circular ending, there is nothing left resembling an ending at all. Tony and Doug do not return to 1968. Project Tic-Toc does not retrieve them. The Tunnel is not shut down. Nobody even acknowledges that their journey might be over.

Their last canonical destination is simply wherever the Time Tunnel sent them after “Town of Terror.” We never see it. And that's where this case has remained since April 7, 1967.

There is something particularly appropriate about THE TIME TUNNEL acquiring a false ending through repetition. For generations encountering the series in reruns, syndication, home video and streaming, Episode 30 naturally feeds back into Episode 1. Finish the series and start it again, and Tony and Doug really do appear to travel in a circle. The accident of television scheduling became something that looks remarkably like artistic intent.

But Cold Cases aren't about finding the most satisfying explanation. They're about finding out what actually happened. So the Titanic cannot close this case. If we want to know whether Tony Newman and Doug Phillips were ever supposed to get home, we have to look somewhere else.

We have to start searching for Episode 31.

PART SIX: COULD THEY HAVE GOTTEN HOME?

Somewhere in the history of almost every prematurely canceled television series is a phantom next episode. In THE TIME TUNNEL's case, the phantom is more substantial than most.

Television historian Martin Grams documented more than 30 proposals prepared for a possible second season. They included stories involving Atlantis, a future Ice Age, alien threats and other time travelers. “Lost Civilization,” a teleplay written during first-season development but never produced, appears to have been considered as a possible Season Two opener.

James Darren also recalled discussing a Jack the Ripper story, although decades later he was careful not to claim more than he remembered. Robert Colbert believed a longer-running series would probably have given Project Tic-Toc greater control over the travelers and might have introduced recurring adversaries or other time travelers.

In other words, there really was an Episode 31 somewhere in the development pipeline—even if there was never a filmed Episode 31.

But none of the surviving proposals solves our case. They show Tony and Doug continuing to travel. They do not show Tony and Doug coming home.

That makes sense from a production standpoint. Bringing the men permanently back to Project Tic-Toc would have solved the problem that generated the series. Once the Tunnel worked well enough to retrieve them, its two wandering heroes risked becoming scientists standing in the control room watching somebody else have the adventures.

The failure to bring them home wasn't merely a problem for Tony and Doug. It was job security.

There were ways around that, of course. They could have returned temporarily and been sent out again. The Tunnel could have malfunctioned in some new way. Another traveler could have become stranded. Irwin Allen television rarely suffered from a shortage of catastrophes.

But none of those possibilities constitutes an ending. We aren't trying to write the finale THE TIME TUNNEL should have received. We're trying to determine whether one was ever planned.

So far, the evidence says no.

Later attempts to revive the property do not help. A substantially reimagined pilot was produced for Fox in 2002, with a new team and a different temporal crisis. It never became a series, and it did not continue Tony and Doug's story.

Project Tic-Toc apparently has trouble getting renewed in every timeline.

But that revival establishes an important Cold Cases rule: a remake is not a resolution. A reboot does not tell us what happened to the people we left behind. Unless a later continuation resumes the original narrative and answers its unfinished questions, the original file stays open.

For Tony Newman and Doug Phillips, no television movie arrived years later to bring them home. No reunion special showed an older Project Tic-Toc finally detecting their coordinates. Their disappearance was never reversed.

Maybe there was never supposed to be a final destination. Maybe Tony and Doug would have continued bouncing through history until the ratings declined, the production became too expensive or Irwin Allen decided he had another spectacle he'd rather build.

If so, ABC's reversal didn't interrupt a planned finale. It interrupted an ongoing mission.

That doesn't get the network off the hook, because the audience had been given an objective from the beginning. Two American scientists were lost in time. Their friends were trying to bring them home. For thirty episodes, they failed. Then ABC stopped giving them chances.

The machine simply went dark.

After almost sixty years, we can find proposed adventures, abandoned ideas and revival attempts. What we cannot find is the one piece of evidence that would close the file: Tony Newman and Doug Phillips stepping through the Tunnel into 1968.

We have to close the investigation without finding the missing men.

PART SEVEN: LOST IN TIME

Cold Cases usually begin with a body. This one begins with two missing persons.

Dr. Anthony Newman and Dr. Douglas Phillips disappeared from a government installation beneath the Arizona desert in 1968. Project Tic-Toc knew they were alive. Its scientists repeatedly located them, watched them and occasionally communicated with them.

They just couldn't bring them home.

For thirty episodes, that failure powered THE TIME TUNNEL.

Tony and Doug survived the sinking of the Titanic. They escaped the destruction of Krakatoa. They witnessed Pearl Harbor, fought at the Alamo, crossed paths with historical figures and survived threats that didn't belong in history at all.

Again and again, Project Tic-Toc found them. Again and again, it lost them. Then, on April 7, 1967, ABC lost them permanently.

There is no evidence that “Town of Terror” was intended as a conclusion to THE TIME TUNNEL. There is no homecoming hidden inside the final episode. The familiar glimpse of the Titanic that followed did not reveal that Tony and Doug were trapped in an eternal loop. It was the machinery of a television series preparing to begin its rerun cycle.

There was no filmed Episode 31. There was no second season. There was no reunion movie decades later to finish the job.

There are documented proposals for further adventures, but no documented final chapter waiting in the evidence box that tells us how Irwin Allen ultimately intended to resolve the problem he created in 1966.

That makes THE TIME TUNNEL an almost perfect first case for this particular division of FINALE INTERRUPTUS.

The crime isn't that ABC canceled a television series.

Networks have been doing that almost as long as there have been networks.

The unfinished business is that THE TIME TUNNEL gave its characters an objective that remained active throughout the series. Tony and Doug weren't merely moving from one self-contained adventure to another. They were stranded. Project Tic-Toc was trying to retrieve them. Every new destination represented another failure to accomplish the mission established in the premiere.

That mission never ended. It was abandoned.

ORIGINAL MISSION: Retrieve Tony Newman and Doug Phillips.

EPISODES PRODUCED: 30.

EPISODES AIRED: 30.

MEN RECOVERED: 0.

CASE STATUS: UNRESOLVED.

VERDICT: COLD CASE CONFIRMED.

Nearly six decades have passed since Project Tic-Toc last looked into the Tunnel.

The control room is dark now. The computers have stopped blinking. The reels have been boxed up, the files have yellowed, and the Project Tic-Toc patch has become another artifact from a future that once looked remarkably like 1968.

But somewhere in television history, Tony Newman and Doug Phillips are still falling through that Tunnel.

The scientists who were supposed to retrieve them never got another chance. The audience that waited for them to come home never got an answer.

So we'll record their last known whereabouts exactly as ABC left them on April 7, 1967:

Somewhere in time.

CASE CLOSED? Not even close.

COLD CASE #001 remains open.