As Endeavour and Thursday deal with the heartbreak of Joan's departure, a death at East Cowley Slipper Baths hurls the pair into another dark adventure.
Endeavour is charged with protecting Joy Pettybon, self-appointed guardian of the nation's morals, who is visiting Oxford to promote her 'Keep Britain Decent' campaign.
When a body is found in a marshland outside of Oxford, everyone assumes they're the remains of Oxford botanist Matthew Laxman, who disappeared near the site five years earlier.