The Avengers – ‘The Deadly Air’ [Series 1 Ep.24 – 1961] – Ian Hendry [as David Keel] and Patrick Macnee [as John Steed]
Picture above: Ian Hendry [as Dr. David Keel] and Patrick Macnee [as John Steed] – The Avengers Series 1 
The Avengers – The Deadly Air
This lovely still looks as though it was taken on the set of ‘The Deadly Air’ in which Keel and Steed carry out an investigation within a laboratory.
Series 1 – Episode 24 – The Deadly Air
By Lester Powell
Production completed: 7 September 1961. First transmission: 16 December 1961
When several experiments with a new vaccine go wrong, Steed and Dr Keel volunteer for the next test. One of the scientists, Heneager, appears to be sabotaging the project and a potent airborne virus nearly kills the Avengers. As Keel interrogates Heneager for the truth, Steed is discovering that Dr Craxton is the real mastermind. Steed is convinced that Craxton has fatally poisoned him, until it is revealed that the lethal vaccine had been replaced by water as a security measure.
Until next time,
Editor, Official Tribute To Ian Hendry
A detailed account of the life and work of Ian Hendry in the new biography: