ALL’s fair in love and war for two US government spies with their hearts set on the same woman in an action-packed comedy from director McG.

This hare-brained buddy movie delivers slam-bang thrills and a few sparkling one-liners as rivalry between the two elite operatives escalates out of control, resulting in amusing abuses of CIA resources.

This Means War starts with a bang and McG knows how to bolt together explosive sequences to quicken the pulse.

However, comic interludes don’t always hit their target and the voyeuristic nature of the men’s surveillance leaves a nasty taste in the mouth, especially when they resort to documenting entanglements in the bedroom.

Crucially, the film’s inherent design flaw – like the heroine, we have to side with one of her suitors – means half the audience will be disappointed by the overblown climax when the love-struck lady makes her choice.

The girl gets her guy, just maybe not the right one.

The film opens with a fast-paced action sequence in Hong Kong, where agents FDR (Chris Pine) and Tuck (Tom Hardy) are out to apprehend crimelord Heinrich (Til Schweiger).

Instructions from their boss to be discreet are gleefully ignored, leading to a high-profile shootout.

The buddies return to HQ to face the music.

To lighten the mood, ladies’ man FDR helps shy and gallant Tuck dip his toes back into the dating pool by creating a flattering profile for his friend on a relationships website.

Soon after, Tuck accepts a first date with the beautiful Lauren (Reese Witherspoon), who is recovering from a break-up.

Tuck is instantly smitten.

Soon after the date, FDR also encounters Lauren and he falls for her acidic wit.

Armed with a dazzling array of hi-tech gadgetry, FDR and Tuck compete against each other to win Lauren’s heart.

She is torn between the two men, unaware they know each other, and seeks advice from her potty-mouthed – and scene stealing – sister Trish (Chelsea Handler), who counsels, “Don’t choose the better guy. Choose the guy who makes you the better girl.”