No Refuge

An armed robbery at the local glassworks leaves an employee dead and £15,000 stolen, and Frost is reunited with DS Maureen Lawson — the partner who got under his skin last season — to work it. The owner, Bill Boxley, identifies one of the raiders, Stuart Penrice, and then the threats begin: a note ordering him to retract his statement, a shot fired at him on the job. Boxley, convinced the police cannot protect him, goes into hiding alone, and his hideout is burned down around him.

Frost and Lawson work the chain of culprits — a former employee, a third man, a betrayal over a girlfriend — until the investigation arrives at its strangest turn. Penrice admits the gang mislaid their shotgun during the raid, and Frost realises who picked it up: Boxley's own son Kevin. The boy who threatened his father was not a criminal; he was a son venting years of fury at a controlling, critical parent who had also seduced the girl Kevin loved. Bill Boxley, confronted at last, apologises for his failures, and Kevin surrenders the gun.

The second case is quieter and crueller. Frost and Lawson investigate a series of burglaries at the house of a lesbian couple, and the culprit turns out to have been living in their loft. But the real damage is emotional: Lawson and the younger partner, Liz, fall into a romance, and when the older partner Marion — heartbroken, possessive, humiliated — stabs Liz, the fallout destroys Lawson's career. Mullett, embarrassed by the connection, forces her posting to a station in Cornwall. It is a sour, realistic ending for a beloved character, and Sally Dexter plays Lawson's grief without a trace of self-pity.

And the personal thread snaps. Shirley's mother dies, Frost pledges to attend the funeral and does not, and Shirley finally tells him what everyone else has been thinking: he is afraid of commitment, incapable of truly investing in a partnership. He ends the relationship, telling her she deserves better. No Refuge, written by Christopher Russell and directed by Don Leaver, is the series' most devastating finale to date — a season that began with romance ending with everyone alone.