When their mother starts to date the mystery man on the fifth floor, who has been instructed by his agent to "eliminate the children" by the first of May, eleven-year-old Caroline and her older brother figure they're targeted to be the victims of a savage crime.

Forced to spend a summer with their father and his "new" family, Caroline, age eleven, and J.P., age thirteen, are given unpleasant responsibilities for which they are determined to get revenge.

Lowry's third novel about J.P. and his sister has J.P. in love and doing all sorts of weird things, such as wearing deodorant and even telling a lie to impress Angela.