Based on ID Software's first-person shooter game, this gory, shameless ALIENS (1986) rip-off dispatches a platoon of future Marines to Mars, where the Olduvai research facility is under attack by apparently unstoppable monsters. Like Doom itself, the movie is rich in backstory, but sparse in actual
story. The Olduvai colony is reached via the Ark, a mysterious portal discovered in the Nevada desert and apparently built by a long-dead civilization whose ruins lie beneath the planet's dead surface. Marine John "Reaper" Grimm (Karl Urban) was raised on Olduvai by his archaeologist parents, who died in an accident; his estranged fraternal twin, Dr. Sam Grimm (Rosa...