Based on a Jack London story, "Sign of the Wolf" concerns an unruly canine who saves his owner and a servant following a plane crash, then aids another dog being trained by thieves to steal fox pelts. Grace Bradley, Darryl Hickman, Mantan Moreland star. Then, in "Crack-Up," Flash the Wonder Dog helps clear his pilot pal's name when the man is falsely accused of pulling off an airport payroll robbery. With David Sharpe, Gertrude Messinger. AKA: "Flash the Wonder Dog: Crack-Up." 85 min. total. Standard; Soundtrack: English. Plays All Regions.