The Chaos Engine 2

During the original game, the protagonists succeed in destroying the Chaos Engine, a time-travel device. Its creator, Baron Fortesque, appears to have been defeated. However, in The Chaos Engine 2, it transpires that he and the protagonists are all trapped within a temporal singularity created by the destruction of the Chaos Engine device. In order to survive they must assist the Baron in rebuilding the device, though only one of them will be able to escape the singularity. (wikipedia)