Time Out says
The most respected assassin in London, Victor (Nighy) is an impeccably mannered, middle-aged bachelor ripe for a makeover. A contract killer like his father and grandfather before him, this gentleman hit man's discretion and professionalism have left him lonely and loveless. That starts to change when he's hired to kill Rose (Blunt), a beautiful, brazen thief who conned a slick gangster (Rupert Everett) into buying a fake Rembrandt. For the first time in his career, Victor is reluctant to pull the trigger.
Gifted a promisingly dark comedic setup borrowed from a French film---1993's Cible mouvante---director Jonathan Lynn (The Whole Nine Yards) banishes any shadow of suspense or devilry for the sake of broad, breezy humor. Gunfights and car chases are defanged by insistently peppy music, underscored one-liners pass for wit, and even Victor's would-be romantic rival, Tony (Grint), turns out to be a sexless apprentice. Even a commendably game Blunt can't sell Rose's implausible progression from petulant princess to moony lover, while thespian sight gags---from Eileen Atkins as Victor's infirm, gun-toting mom to Martin Freeman as a natty sadist with bleached white teeth---expose a script short on ideas. It's entertainment designed to resemble a good time without aspiring to provide one.
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