Archie's lab accident creates a black spot that hops from person to person, giving them the temporary ability to pass through solid objects.; Archie wants to date a new girl, if he can pass inspection from her eccentric father.; Miss Grundy becomes incensed when she overhears Archie and Reggie assigning number values to the girls they've dated.; Archie tries to con his way out of a home maintenance job, but finds his father two steps ahead of him.; The house is quiet and that makes Hap nervous.; Jughead has an accident. Archie borrows Miss Grundy's screen.