The tools in a spy's arsenal are more varied than you might think. But they all come under one name: Tradecraft. In our fourth round of insights from the world of espionage, Vanessa Kirby meets brave investigators, wily whistleblowers and whip-smart spycatchers in the ultimate digest of the series so far. Could YOU master the craft? From SPYSCAPE, the HQ of secrets. A Cup And Nuzzle production. Series producer: Gemma Newby, Joe Foley. Produced by Alex Burnard. Music by Nick Ryan.