Appropriate adults: Concerns the mystery of a missing 8 year-old girl who was last seen by a young man with Down’s Syndrome. Frost’s superiors believe the young man is guilty, but Jack takes a different lead to find the girl’s kidnappers.

Quarry: An animal rights group protests a foxhunt in Denton and one of the activists is found murdered. Detective Constable Clive Barnard, the chief constable’s nephew, returns to help solve the case. Jack gets closer with Shirley Fisher..

Dead Male One: The mystery of a murdered man in the river deepens when Frost discovers that the man’s driver’s license actually belongs to someone else. A star player on the local soccer team collapses during a press conference. Was he poisoned? Jack and Shirley Fisher take a big step in their relationship.

No Refuge: Multiple burglaries in the same home lead Frost to a surprising arrest. Jack and a female detective sergeant are called to a local factory where a robbery and murder have been committed. The owner identifies a suspect but goes into hiding when his life is threatened.