It's the start of 1971 - though wearied from the events of the past year, there's no chance of "light duties" at the CID. Crestfallen and rarely without a scotch in hand, Endeavour finds himself right back in the thick of it when an explosive murder at an Oxford college has potentially far-reaching political ramifications. Meanwhile, the IRA have made a threat against the life of the Oxford Wanderers' star striker, and Endeavour is tasked with the duty of acting bodyguard.