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The Avengers: 6x29

Requiem

When Steed takes prime witness Miranda Loxton to a safe house to protect her from Murder-International hitmen, Tara is kidnapped. She escapes to find herself in her worst nightmare. A booby-trap in Steed’s apartment kills Mother and Tara may be the only one with the hidden knowledge of where Steed has gone.

The Avengers: Season 6 Episode 29
Mar. 31, 1969