It's 1957, and Will Davenport has settled into his role as the vicar of Grantchester, preaching to a packed church. His best friend, Detective Inspector Geordie Keating, has come to accept his wife Cathy's commitment to her job – just about. Mrs C. happily juggles her roles as the vicarage housekeeper and being a well-to-do married woman, and after a trip to Marrakech, even Leonard has managed to carve out some happiness with Daniel. But Will's faith will be thoroughly tested as he and Geordie are reminded once more that there's darkness lurking in their little corner of Cambridgeshire...