Lady Sannox, the toast of London society, carries on an obvious affair with Douglas Stone, an arrogant, young surgeon. Lord Sannox, a retired star of the stage, is thought to be a clueless old man unaware of the liaison. After discussing with the Lady his plan to murder her husband so they can marry, Stone is hired by a desperate man to perform a questionable operation on his wife. Lord Sannox, we learn, is not as oblivious to his wife's infidelity as he appears. (thetvdb.com)