Space Quest IV: Roger Wilco and the Time Rippers is a humorous graphic adventure created by Sierra On-Line. It is the fourth chapter of the popular Space Quest series; a saga started with Space Quest I: Roger Wilco in the Sarien Encounter.
Space Quest 4 was released initially in 1991 for PC and Macintosh and then ported to Amiga and PC CD-ROM in 1992. It featured 256-color hand-painted graphics and motion capture animation. The game is entirely mouse-driven and uses Sierra's icon-based SCI interface.