"Time and Time Again" is a Time Travel Short Story written by H. Beam Piper which was published in the April 1947 issue of Astounding Science Fiction. It was his first published work.
During the Third World War in 1975, Allan Hartley, a 43-year-old captain attached to the Scientific Warfare division of the General Staff, is critically injured as a result of an explosion. After being given a narcotic injection, he becomes "lost in a great darkness" and suddenly finds himself in his 13-year-old body in Williamsport, Pennsylvania on August 5, 1945, the day before the United States dropped the first atomic bomb on Hiroshima. Using his knowledge of the next 30 years, Allan plans to alter history and prevent the war from ever happening.
The short story was adapted as episodes of the science fiction radio series Dimension X in 1951 and its Spiritual Successor X Minus One in 1956 using the same script by Ernest Kinoy.
The short story provides examples of:
- Cunning Linguist: Allan is highly proficient in French and Spanish (though he has "a Mexican accent you could cut with a machete") and knows a little German and Russian.
- The Fundamentalist: Frank Gutchall in spades.
- Hiroshima as a Unit of Measure: Allan claims that the bomb that will be dropped on Hiroshima the next day is a firecracker compared to the one that killed him during the Battle of Buffalo, which exploded ten miles away.
- Peggy Sue: After being fatally injured in the Battle of Buffalo during World War III in 1975, Allan's 43-year-old mind is sent back in time to his 13-year-old body on August 5, 1945. Allan speculates that the mental transfer may have been caused by the bomb blast that injured him, the narcotic injection that he was given, something unforeseen in 1945 or a combination of all three.
- Set Right What Once Went Wrong: In the original history, the lay preacher and religious fanatic Frank Gutchall murdered his wife using a Colt-.38 special that Allan's father Blake had loaned him on August 5, 1945. He claimed that he needed it to put his injured dog out of its misery. Remembering the original incident, Allan gives Gutchall his father's Luger after removing its firing pin. He then calls the police station, pretending to be his father, and tells them that Gutchall is planning to kill his wife. Gutchall is arrested and eventually committed. Allan saved Mrs. Gutchall's life as an experiment to determine whether the future could be altered. Armed with the knowledge that it can be, his plan is to start a political organization in Pennsylvania in 1950 with the goal of electing Blake to the presidency in 1960 and preventing the outbreak of World War III.
- Shared Universe: The story is set in the same universe as two later Piper works, "The Mercenaries" and "Day of the Moron". Both stories, which take place in 1965 and 1968 respectively, refer to President Blake Hartley, indicating that Allan's plan to get his father elected in 1960 was successful and an Alternate Timeline was created. The former reveals that Blake served as the President of the chemical company Associated Enterprises before his election but the real power lay with Allan. Kato Sugihara speculates that the same is true with respect to the government.
- Shown Their Work: The story was written less than two years after the majority of it takes place but Piper's research is nevertheless in evidence. Allan reads the August 5, 1945 copy of The New York Times which contains stories concerning a B-25 Mitchell bomber crashing into the Empire State Building (on July 28), the end of the Potsdam Conference (on August 2) and the continued bombing of Japan from the air and shells from off-shore naval guns. Allan later recalls the announcement of Japanese surrender came at exactly 7:01pm on August 14, 1945.
- Time Travel for Fun and Profit: Allan plans to raise primary capital for his father's campaigns by placing bets on the winners of the Kentucky Derby, the Preakness Stakes and the Belmont Stakes and by using his knowledge of future developments in chemistry to establish a company that will overshadow IG Farben.
- 20 Minutes into the Future: The United States and Canada are embroiled in World War III in 1975. Allan traces the origins of the conflict to 1960 with the election of a "good-natured nonentity" as U.S. President. This President proved ineffectual and his poor handling of international relations made the war inevitable. More minor references to future events include Allan and his childhood friend Larry Morton graduating from Penn State and Cornell respectively in 1954 and Larry being killed in a plane crash in 1968.
- World War III: The Third World War began in or before 1975. A transpolar invasion of Canada led to the fall of Ottawa. As such, the US forces in Canada were forced to retreat but they made their stand at Buffalo, where Allan was killed. It is never specifically stated what country or countries the United States and Canada were fighting.
The radio adaptation provides examples of:
- Adaptational Alternate Ending: In the short story, the transfer of the 43-year-old Allan's mind into his 13-year-old self's body is seemingly permanent. In the radio adaptation, the process reverses after only a few hours and the older Allan dies in both body and mind in 1975. As such, the radio version leaves it ambiguous as to whether Blake will succeed in being elected President in 1960 and preventing the war. While he only has a vague impression of the events that the next 30 years will bring, he is determined to save his son's life. Blake also has the list of the race winners up to 1970 that Allan gave him before his mind returned to the future so he can still raise the necessary capital.
- Adapted Out: The Hartleys' German housekeeper Mrs. Stauber is left out of the radio adaptation.
