Since the death of their mother in a hit-and-run accident, Violet and Jane have been living with their 'young-at-heart' great-grandfather, the charismatic Luke Grant and his partner Helena. One evening Violet's boyfriend, Roddy, doesn't arrive to take her on a date and the next morning his mother turns up looking for him. Whilst Violet and Roddy's mother panic, the ever practical Jane takes the family dog to hunt down the missing Roddy. When she finds him, badly injured and unconscious, having fallen down a disused well, it seems that foul play was involved and the police are brought in to investigate. The trail leads them to the local youth centre where Roddy was a volunteer and then Luke is persuaded to help follow the suspects to the island of Madeira and uncover a bizarre and unscrupulous scam...