Nursing his terminally-ill wife, Det Insp ""Jack"" Frost's life becomes more stressed when, during a missing-child investigation, he unearths evidence on a 30-year-old case involving a skeleton chained to a locked strongbox that turns out to be empty.

An odd group of animal rights advocates attempting to sabotage a foxhunt includes a working-class teenager, who is murdered. Then another person associated with the anti-hunt protesters is murdered. His investigations take Frost to tea with a local squire, but Supt Mullett is apprehensive lest he upset the gentry.