The Three Investigators in The Secret of Terror Castle

A videotape turns up during Jupiter Jones's birthday party in Rocky Beach, and on it are his long dead parents, speaking straight to him. Jupiter (Chancellor Miller), Pete (Nick Price) and Bob (Cameron Monaghan) have to work out the riddle their message leaves behind. Florian Baxmeyer sets the boys at the center, three friends bent over the tape, the party still going on around them.