Trinity was the 20th game released by interactive fiction pioneers Infocom. It appears on several lists of the greatest video games of all time.
Game designer/programmer (or as the company called it, "implementor", or "imp") Brian Moriarty had previously produced Wishbringer for Infocom. Moriarty engaged in an exceptional amount of research to create Trinity. This included consulting dozens of books (as described in a bibliography contained within the game manual), as well as many interviews. On the 40th anniversary of the Trinity experiment in 1985, Moriarty was also granted an in-person tour of the Los Alamos lab in New Mexico, guided by the author of a respected book about the Manhattan Project.
Trinity is an elliptical trip through time and the history of the atomic bomb.
At some unspecified time in 1986's near future, the player is spending a peaceful day in Kensington Gardens, London, unaware that the area is about to be hit by a Soviet nuclear missile attack. Just as the bomb is about to detonate, the player discovers a mysterious door floating in mid-air.
The door leads to an area called "the Wabe". This is a reference to Lewis Carroll's poem "Jabberwocky". Carroll describes a "wabe" as "the grass plot around a sundial", and there is indeed a giant sundial here, surrounded by toadstools. Each toadstool represents a different, historically important nuclear explosion. Using a gnomon (the part of the sundial that casts a shadow) acquired in Kensington Gardens, the player is able to point the sundial towards a toadstool and open a door in space-time to travel to the circumstances of that explosion. Each event requires fantastical puzzles to be solved in order to proceed. The game is also noted for its understated, melancholy tone and abundant literary references.
In addition to Kensington Gardens (the last, or "omega", entry on the sundial), the historical events that can be visited are:
- July, 1945: The original Trinity Site test
- August, 1945: The atomic bombing of Nagasaki, Japan
- 1949: The Soviet Union's first successful atomic bomb test
- 1952: The first test of the more powerful hydrogen bomb, at Eniwetok Atoll in the Pacific Ocean
- 1970: An "Operation Emery" underground test, beneath Nevada
- Near future: A low-earth-orbit test of a nuclear missile defense system, analogous to Ronald Reagan's "Strategic Defense Initiative" (or "Star Wars") project
Ultimately, the player is able to "sabotage" the original Trinity test. This theoretically prevents an uncontrolled explosion that would have destroyed the entire state of New Mexico, but since -- as the game puts it -- "Nature doesn't know the word 'paradox'", history as we know it is not changed. The player is then returned to Kensington Gardens, again as the bomb is about to hit.
As had become traditional for Infocom, Trinity's packaging contained collectibles (or, as they were referred to, "feelies") to help set the mood of the game. Trinity's "feelies" were:
- A map of the Trinity site.
- The Illustrated Story of the Atom Bomb, a 14-page-long "educational" comic book. The comic book's jingoistic depiction of history stands in stark contrast to the elegiac tone of the game.
- A cardboard sundial, analogous to the one found in the game.
- Instructions for folding an origami crane. Also a motif in the game, this is a reference to Sadako Sasaki, a young girl who was a victim of the Hiroshima atomic bombing. Japanese legend held that anyone who folded 1,000 origami cranes would be granted a wish. The ailing Sadako was able to exceed this number, but died at age 12 of leukemia caused by radiation from the bombing.