Trinity

Trinity is an interactive fiction computer game written by Brian Moriarty and published in 1986 by Infocom. The plot blends historical and fantastic elements as part of a prose poem regarding the destructive power of the atomic bomb and the futile nature of war in the atomic age. The name refers to the Trinity test, the first nuclear explosion, which took place in July 1945.

You're neither an adventurer nor a professional thrill-seeker. You're simply an American tourist in London, enjoying a relaxing stroll through the famous Kensington Gardens. When World War III starts and the city is vaporized moments after the story begins, you have no hope of survival. Unless you enter another time, another place, another dimension. Escaping the destruction of London is not the end of your problems, but rather the beginning of new, more bizarre riddles. You'll find yourself in an exotic world teeming with giant fly traps, strange creatures, and other inconveniences. Time and space will behave with their own intricate and mischievous logic. You'll visit fantastic places and acquire curious objects as you seek to discover the logic behind your newfound universe. And if you can figure out the patter of events, you'll wind up in the New Mexico desert, minutes before the culmination of the greatest scientific experiment of all time: the world's first atomic explosion, code-named Trinity.