Fair Game (S04E08)

Susanna Temple Richards, portrayed by Jenny Agutter, is embroiled in an affair with a local man. Her husband, frequently seen drinking, becomes a target as Susanna slips sleeping pills into his whisky to ensure he won't disrupt her plans for a hunt the following day. To her surprise, he shows up anyway, only to suffer a fatal fall while riding and hits his head. An investigation reveals a high concentration of sleeping pills in his system, leading to Susanna's arrest. Meanwhile, with Archie Cutter deceased, Claude asks Nick to tend to his poultry, which Blaketon later reveals is linked to Archie's shady reputation as a cockfighter.