Release Message:  Four shaken and discontent survivors join the people inside the lighthouse where the Doctor (Tom Baker) surmises they're all being carefully scrutinized, a prelude to an attack.

Description:  With inexplicable electrical problems keeping the lighthouse from maintaining a steady beam, a foolhardy ship crashes against the island rocks. Four shaken and discontent survivors join the people inside where the Doctor surmises they're all being carefully scrutinized, a prelude to an attack.