It Happened Tomorrow is a 1944 American fantasy film directed by René Clair, starring Dick Powell, Linda Darnell and Jack Oakie, and featuring Edgar Kennedy and John Philliber. It is based on the one-act play "The Jest of Haha Laba" by Lord Dunsany.

Lawrence and Sylvia Stevens are celebrating their 50th wedding anniversary. In a flashback to the 1890s, Lawrence Stevens is an obituary writer unhappy with his job. He is given tomorrow's evening newspaper by an elderly newspaper man named Pop Benson, though he does not bother to read it.

After work, he and his co-workers go to see a mind-reading act starring the "Great Sigolini" (Oscar Smith) and his beautiful assistant Sylvia. Lawrence is enchanted with Sylvia and manages to get her to agree to a date the next day. He finally notices the newspaper's date, but dismisses it as a mistake. However, he notes the weather forecast is for an unseasonable snowfall, which occurs, and later an advertisement for a waiter which precedes the firing of one. Then he reads about a robbery at a theater's box office during a performance in an article under his byline. He writes the article beforehand. His editor refuses to publish it at first, until a policeman comes by and confirms the robbery.

This causes Police Inspector Mulrooney to put him in jail, convinced he could only have known about the robbery by being a member of the gang who pulled it off. Stevens and his new girlfriend Sylvia have a number of adventures, until her uncle mistakenly thinks that Stevens has consorted with his niece in her boarding house room. The uncle attempts to intimidate Stevens into marrying her, not knowing that Stevens has come to him to ask for her hand.

Stevens gets another newspaper from Pop Benson, intending to use it to pick horses at the racetrack, to win enough money to get married. Unfortunately, he also reads a story about his own death that night, so he and Sylvia get married immediately and head off to the track with her uncle. Stevens bets on winner after winner, amassing $60,000, which is then stolen on their way back to town. They give chase but are arrested for speeding. Stevens hopes for more help from Benson, but learns that the old man died two days ago, even before Stevens received the first newspaper.

Stevens tries his best to avoid the hotel lobby where his death is supposed to take place, but circumstances keep pushing him in that direction. He spots the man who stole his money and chases him on foot through the streets and over the rooftops, until they both fall through the chimney that leads to the very hotel lobby he's been trying to avoid. A gunfight breaks out, and the thief is shot and killed. Because he has Stevens' wallet on him, he is at first identified as the newspaperman, and his newspaper prints an erroneous story saying that their star reporter has been killed. When a reporter finds out the truth, the newspaper has already hit the streets; and it is this edition that he had received from Pop.

Stevens does not die in the hotel lobby, and he and Sylvia celebrate their 50th wedding anniversary with the scene that begins the film.

Director and producer Frank Capra originally purchased the rights to Hugh Wedlock and Howard Snyder's story, but when he discovered the concept was similar to that in Lord Dunsany's 20-year-old one act play, he bought it as well; later, when he was going into the Army to serve in World War II, he sold both to Arnold Pressburger. Pressburger approached René Clair about directing the film, and the two hired Clair's friend Dudley Nichols to assist in writing the script. They set the time period in the 1890s to avoid dealing with the war.