New recruit Sergeant Callum Stone makes an instant impact at Sun Hill by subduing a violent drunk in the station, but his maverick methods instantly alarm Dan and raise Smithy's hackles. Terry, Sam and Kezia trace a series of threatening calls made to elderly women back to a single suspect, a supervisor at a kitchen fitting company, who is less than pleased to be arrested in a lift stalled between floors. Stone investigates the circumstances leading to the collapse of a woman brought in to the station by Dan and Tony.