"The Night of the Bleak Island" is the 21st episode of The Wild Wild West 's fourth season, airing on March 14, 1969, and featuring a mystery plot inspired by And Then There Were None . James West, operating without Artemus Gordon, uncovers that guest Sir Nigel Scott is using a trained hound to kill heirs for a diamond, as detailed in the episode's plot. For the detailed episode outline, visit IMDb . The Night of the Bleak Island - IMDb