After being the only witness to a car crash on a country road, Sam answers an abandoned mobile telephone and hears a message that was not meant for him. He is encouraged by the office mailroom delivery boy that they can be the heroes but soon find themselves plunged into a shocking kidnap situation.
Nick Stevens is heavily in debt to Mr Lau, a local underground casino boss who has now kidnapped his wife Scarlett. With no money, no skills and no idea, Phil and Sam are sent to rescue her by the cowardly Stevens. Sure enough, it doesn't go very well, and in the melee our heroes end up accidentally taking an angry hostage of their own.
Sam attempts to negotiate the exchange of Scarlett from Mr Lau with his nephew Jason, but Phil accidentally ruins the plan. Following a dramatic escape, they take Scarlett home to her husband. Sam and Phil then need to go on the run from both the police and the criminals. They end up finding some temporary safety with MI5 agent Walker.
The devious Scarlett sends Sam and Phil on a mission to retrieve a music box, which has fallen into the hands of eccentric Russian exile Marat Milankovic. Armed only with the ransom money they found in the back of Walker's car, the duo set off to buy it back. But with the vengeful Lau still seeking payback, Sam and Phil find themselves arriving empty-handed at a drug-fuelled house party. Inadvertently stumbling into the middle of a poisonous assassination plot, the boys are plunged deeper into a world of betrayal, bullets and blood.
Sam and Phil take Marat back to Phil's house where his mother proves to be very resourceful. With spies shadowing their every move though, and with MI5 closing in on them, the duo begin to work out what's afoot and they become high-value fugitives.
Sam and Phil are now on the run and as their friends and family get caught up in the conspiracy, their limits are pushed. They soon realise the only way to save everyone is to put themselves on the line.