Slidecage

S4, E9: Quinn calculates the coordinates to his and Colin's home world; now they will finally meet their birth parents -- and find out how to defeat the Kromaggs. When they leap into the vortex, however, they land in a labyrinth on a barren, alien world. They discover that the timer has stopped counting down and has frozen at 00:00. The Sliders soon come across a video presentation by Michael Mallory, Quinn and Colin's father. He explains that they have been deposited here by the "Slidecage" mechanism, which cloaks the homeworld from further invasion by the Kromaggs. Unfortunately, it also keeps them from ever leaving.