One of the great openings in episodic television: a desperate man in
tropical gear wading through a swamp, hacking underbrush, climbing a wire fence. As he's about to escape, a dart hits him in the back and falls by a road marker, "London 23 miles."
Steed (Patrick Macnee) brings Mrs. Peel (Diana Rigg) to a house in darkest Hertfordshire, where the comatose man is being treated for sleeping sickness. He's not the only case. Emma Peel recruits Professor Swain (Liam Redmond), who insists the illness results from Shirenzai, a magic cult indigenous to a former British colony, "Kalaya."
As it happens, there's an adjacent Kalayan Ex-Servicemen's Club, and Steed goes to investigate. Our heroes encounter Razafi (Paul Danquah), a seemingly sinister Kalayan in warpaint.
In an era when Brian Clemens claimed The Avengers would "never show a coloured man," this episode features Danquah, son of a Ghanaian official, as well as beautiful transplanted Jamaican Esther Anderson as Lala. British colonial apologists might not enjoy Philip Levene's script.
In fashions, Pat Macnee looks sharp in a chalk-stripe suit and then a classic white tropical ensemble. Diana Rigg gets crisp white slacks while her sleeveless black top showcases her broad shoulders. Less stylishly, she wears another of her torpedo padded bras, already outdated. Anderson easily bests Rigg at filling out a sarong, though Diana looks nice.
The episode isn't perfect. As Col. Rawlings, Bill Fraser wolfs down the dense scenery. The action scenes are poorly staged to the point of having Steed (stuntman Rocky Taylor) swing in on a vine to an accompanying Tarzan call. But feeble humour only slightly distracts from the strong plot.