When Keel attends a health conference in Geneva he is unaware that he is carrying, in microdot form, a vital new medical formula - unaware, that is, until he is arrested for murder.

The disappearance of an albino elephant from Noah Marshall's zoo seems to be linked to Steed's investigation of ivory dust in a gun shop. Steed sets out to rescue Cathy from the tiger's cage, find Snowy and investigate the ivory smugglers.