A serial killer has begun murdering bank managers. BBC radio crime correspondent George Cragge gets involved after fielding calls from the killer while broadcasting on Radio 4.
After murdering an MP in the House of Commons, the killer makes a veiled threat to maverick George Cragge, who is closer to the killer than his police counterpart DCI Jefferson.
With a serial killer striking at the heart of the establishment, the Reform Party stands poised to make political capital in the final episode of the satirical comedy drama.