It starts out with an intro movie that you won't soon forget. It's played to "The Thing I Hate," by Stabbing Westward, which is a great way to start off the game. The game's graphics are good for ps1, and there are different settings. The first one is LA, which Duke will visit throughout the game. Aliens have invaded earth, and use a time machine to go back in time and wreak havoc. Duke goes after them. The first place you must visit is the old west. Then there's also Medieval England, and Ancient Rome. There's a boss for each time area, and they're all AWESOME!
Duke Nukem has a large collection of guns to use, including hand guns, shotguns, crossbows, pipeboms, and other very cool weapons.
The enemies include the classic Duke enemy-the pigcop, Drak lizard-like forces, machine-gun patrol robots, and others.
The multiplayer is 2-player split screen, and has 6 levels to choose from. The multiplayer arenas are well developed, and very cool. They have hidden secret areas with weapons and inventory items.
The game has lots of inventory items that you will need to use throughout it. The Jetpack will allow you to fly around the levels, and even burn up enemies below you. The game also has items like night vision goggles, medkits, and gasmasks.
I would definitely recommend Duke Nukem: Time To Kill because it just plain rocks!