Probably encouraged by the success of the movie adaptations of some of his novels Michael Crichton had a go at directing in the 70s and 80s, beginning with Pursuit (1972), adaptation of his own novel Binary (written as John Lange, and credited as such). Then followed Westworld (1973), the adaptation of Robin Cook's novel Coma (1978), The First Great Train Robbery (1978), Looker (1981) and Runaway (1984). He stopped directing after Physical Evidence (1989) did not harness much success, and concentrated in his successful fiction writing career.
In 1999, however, he sat again in the director's chair for some uncredited reshoots for The 13th Warrior, the adaptation of his novel Eaters of the Dead, after the studios broke up with the director John McTiernan due to "irreconcilable differences".