"Back There" is the 49th episode of The Twilight Zone.
"Witness a theoretical argument, Washington, D.C., the present. Four intelligent men talking about an improbable thing like going back in time. A friendly debate revolving around a simple issue: could a human being change what has happened before? Interesting and theoretical, because who ever heard of a man going back in time? Before tonight, that is, because this is - The Twilight Zone. "
On April 14, 1961, young professor Peter Corrigan is involved in a discussion with colleagues at the Potomac Club on the question of whether events in history could be changed if time travel were possible. After bumping into an attendant named William on the way out, Peter feels faint. Confused by the gas lamps and horse-drawn carriages on the street, he notices that he's wearing clothes of a much older style and decides to walk home. He finds that his "home" is a boarding house, and in discussion with the strangers he meets there, he discovers that it's April 14, 1865, the day of Abraham Lincoln's assassination.
Peter rushes to Ford's Theatre to warn everyone but is arrested for disturbing the peace. The police presume him to be a Union soldier under emotional distress. After being held in the police station a short time, he is released into the custody of a man named Jonathan Wellington. Peter continues to implore Wellington and anyone else he can find to do something to warn and protect the president. Mr. Wellington offers Peter a drink, and immediately afterwards, Peter realizes that he has been drugged, presumably because Wellington doesn't believe him and wants him quiet.
After Wellington's exit, Peter crawls to the door, but he passes out before he can warn anyone else. When someone comes in and rouses him, he notices that the handkerchief left behind by "Wellington" bears the initials JWB. John Wilkes Booth himself had drugged him to prevent any interference in fulfilling his mission. As he hears the crowd outside spreading the news that the president has just been shot, Peter realizes it is too late. He was unable to change the past.
Peter runs out and finds that he is back in 1961. Unable to explain the shift in time but knowing that he will now be in familiar surroundings, he returns to the Potomac Club and asks for William. His request for an attendant named William is met with only confusion. Back at the table with his colleagues, he finds that the scholarly discussion has moved from time travel to a new topic and William is at the table participating. When this "new" man of distinction is asked, he reveals that he inherited his wealth from his great-grandfather, a policeman who had insisted despite all opposition that there was an assassination attempt on the president that evening. He had been the only person to believe Peter, had made a name for himself trying to stop the assassination and had become a millionaire.
For Peter, the question of whether past events are unchangeable via time travel is no longer speculation. He states that some events can be changed, and others can't. Overwhelmed by all that has happened, Peter steps aside to wipe his brow with his handkerchief and notices the initials: JWB.
"Mr. Peter Corrigan, lately returned from a place 'back there,' a journey into time with highly questionable results, proving on one hand that the threads of history are woven tightly, and the skein of events cannot be undone, but on the other hand, there are small fragments of tapestry that can be altered. Tonight's thesis to be taken, as you will - in The Twilight Zone."
Preview for Next Week's Story
This, in the parlance of the 20th century, is a used car lot - a graveyard of some active ghosts who, by virtue of some exceptional salesmanship and an Indian rubber stretching of the truth, remain as commodities in a world that, by rights, they should have left generations ago. Mr. Jack Larson plays the role of a larceny-loaded con man suddenly prevented from telling a falsehood. Next week on The Twilight Zone, a most bizarre tale that we call "The Whole Truth".
- "Back There" was adapted as a short story in one of the Twilight Zone anthology books except it had a different ending. Instead of a handkerchief, Corrigan found the only unused ticket from Ford's Theatre.