The Girl from U.N.C.L.E.

The Garden of Evil Affair (1x8)

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A doctor developes a serum that is able to transfer the mind of a dead person into the brain of one of his descendants. The doctor is murdered by members of a cult who kill by scratching their victims. The Cambodyses cult are fed small amounts of poison on a daily basis until they are immune to its affects. However, it renders their finger nails deadly weapons. The cult, Thrush, and UNCLE want the serum and the doctor's granddaughter.