A lightning bolt strikes the vortex during a slide, damaging the timer and trapping Quinn on the astral plane. Now the Sliders are stranded on a world with 1950s technology and Quinn can not be seen by the others. He tries to get the help from the only one who can see or hear him, a girl that has a history of hearing voices.

Poirot and Hastings are at Lake Windermere for an attempt on the world speed-boat record. Two sisters have premonitions of danger. Soon a rich elderly widow is hurt by falling down stairs, then later she is killed by poisoning with phosphorus. The "dumb witness" Poirot must fathom to solve the mystery is a dog.