Melissa McCarthy is at her hilarious best in this rib-tickling espionage spoof.

A desk-bound CIA analyst who becomes an unlikely field agent, McCarthy gets into a series of slapstick comic scrapes as she hops from the US to Paris, Rome and Budapest in pursuit of a stolen nuclear bomb, reluctantly adopting a string of frumpy undercover identities en route.

The infectiously entertaining story sees her rising to the mission’s challenges, gaining confidence and proving her worth to the doubters around her.

It’s McCarthy’s show, but there’s also plenty of room for the supporting cast to shine. Jason Statham is a hoot as an absurdly overconfident hard man, Jude Law is a dashing, debonair spy, Rose Byrne is a haughty, arms-dealing villain, Allison Janney delivers a drily deadpan turn as a CIA spymaster and Miranda Hart is genially bumbling as McCarthy’s fellow desk-bound colleague who joins her in the field.