The so called ‘permissive society' comes under the spotlight as Endeavour is tasked with protecting conservative social activist, Joy Pettybon, after she receives a death threat while visiting Oxford to promote her ‘Keep Britain Decent' campaign. Also staying near Oxford and recording their new album are a band called The Wildwood and their manager Ralph Spender, who is desperate to maintain their squeaky-clean image in the media spotlight. However, their harmony is disrupted when the body of local brickie, Barry Finch, is discovered in the middle of Oxford and it transpires that Finch was working at Maplewick Hall, where they band are staying, before he died. Delving into the social revolution of the time, Endeavour finds himself caught in the crossfire of bitter liberalising forces and deep reactionary conservatism both fighting for the consciences of the British people in 1967. And in this collision of two worlds, Endeavour must explore all avenues before more killings occur.