You shoot first and ask questions, uh, never in this first-person action game that quantum-leaps between such time locales as the Wild West, the Roaring ’20s, and a 25th-century space station. While the environments are beautiful, the hackneyed time-travel story line feels shoehorned into the experience. The split-screen multiplayer mode is great mindless fun, a la Quake. Still, there’s much lost potential in the single-player game. This could have been the next Half-Life, but the overall experience ends up feeling a bit half-baked.