hat goes on inside the head of a killer? This essential yet unknowable question looms large over David Fincher’s filmography. It’s what drives Brad Pitt and Morgan Freeman’s odd couple detectives in their pursuit of self-mythologizing martyr John Doe in . It’s the motivation behind the desperate manhunt carried out by Jake Gyllenhaal’s obsessive cartoonist-turned-amateur sleuth in . It’s what underpins the profiling techniques developed by Jonathan Groff and Holt McCallany’s FBI agents in . And it’s a question that reaches its apotheosis in , a precision-tooled thriller about an enigmatic assassin, played with steely fervour by Michael Fassbender, who embarks on an international revenge mission after missing his latest mark. But feels somehow different to Fincher’s earlier surveys of sociopathic individuals. Reuniting with screenwriter Andrew Kevin Walker to adapt Alexis “Matz” Nolent and Luc Jacamon’s cult French-language graphic novel series, the director has opted for something lighter this time around. A darkly comic, distinctly modern B-movie with old-school inspirations that invites you to step inside a methodical, murderous mind that just so