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To any herpetologist who was alive in the 1950s or 1960s the name Maxwell Knight will need no introduction. For all others: he was a founder member of the British Herpetological Society, author of numerous natural history titles (including How to Keep a Gorilla) and a popular BBC broadcaster appearing on Nature Parliament, Country Questions and The Naturalist. Herpetology (the study of reptiles and amphibians) was his specialty, and he skilfully conveyed his advice and knowledge in his books and broadcasts.

It is the contrast between his life as a spycatcher and early environmentalist that intrigues. He lived two very separate, but equally influential, lives. His MI5 work reached the ears of Winston Churchill during the second world war, whilst later in life he had the respect of his naturalist peers, which included the professional zoo community and wildlife charities in addition to being given a platform by the BBC to broadcast to the nation.

His filing cabinet was left in the safekeeping of Professor John E. Cooper, who in his youth knew Knight very well. Their friendship was strong enough for him to consider Knight as his mentor, and they remained good friends until Knight’s death in 1968.