Honey, We're Past Tense

S2 E7: The Szalinskis and their neighbors the McKennas team up for a weekend camping trip, and Wayne can’t wait to try out the Szalinski Bivouac in a Box, a.k.a. BIVIAB (pat. pending). When a big storm hits the campground, both families pile into the BIVIAB for the night. After a fierce lightning storm, they awaken the next morning to a beautiful day -- thousands of years in the past. Apparently the electrical fluctuations utilized the BIVIAB’s structural configuration as a grounding pole, transporting the tent and its occupants through a time wrinkle. There, the families encounter a clan of cave people menaced by a ravenous tyrannosaur.