When Tom Burke was working on Joanna Hogg’s 2019 film The Souvenir, he found himself growing increasingly irascible. He was playing Anthony, a charismatic, Oxbridge-educated civil servant with a secret heroin habit that drove him to steal from and lie to his girlfriend. He still isn’t sure whether his darkening mood was a result of the character seeping into his subconscious or if it was entirely unrelated. “I might just have been going through some sort of enormously dark,…

