Experienced manservant Barrett (a superbly sinister Dirk Bogarde) starts working for foppish aristocrat Tony (James Fox, Performance) in his smart new townhouse. Much to the chagrin of Tony's girlfriend (Wendy Craig), Barrett slowly insinuates himself in the house and manipulates his master by slyly rearranging the décor. The arrival of Barrett's alluring and sexually permissive 'sister' (Sarah Miles) fatally severs the class barriers and the boundaries between master and servant, as Tony succumbs to the will of his stronger adversary.