Doctor Who The Power of Kroll (VHS Cover) This product represents a VHS cover for the television episode "The Power of Kroll," which is part of the long-running British science fiction series, "Doctor Who." In this story, the Fourth Doctor and his companion Sarah Jane Smith visit the swamp planet of Gelthorpe to retrieve a stolen TARDIS component. There they encounter the fearsome Kroll, a sentient slime that feeds on emotional energy and can manifest physical forms. The cover likely features illustrations or images from this episode, providing a glimpse into its fantastical setting and monstrous antagonist.