Part-time office temp Todd Margaret is unexpectedly chosen to lead the U.K. launch of Thunder Muscle, a new North Korean energy drink of suspicious contents. Despite the help of his new acquaintances Dave and Alice, Todd struggles to make inroads.

Todd's new boss, Brent Wilts, turns up the heat to sell Thunder Muscle, so Todd hatches a plan to crack the British retail market. However, he leaves the practical execution to Dave because Todd has scored what he thinks is a first date with Alice.

Todd decides to launch Thunder Muscle with an advertisement featuring a celebrity endorsement - Dave sets up the meeting. Meanwhile Todd's "relationship" with Alice goes to the next level: dinner at her flat.

Just in time for Wilts arrival in London and demanding all of the money from Thunder Muscle sales, Todd oversees the filming of his commercial and it seems he finally makes a breakthrough but not quite.

With Wilts now maniacally demanding results, Todd finally takes initiative with a publicity stunt guaranteed to get Britain buzzing about Thunder Muscle. Meanwhile, Todd's former boss, Doug, is embarking on an investigation into Wilts' past.

Todd's world is falling apart, so he makes a final desperate bid for Alice's affections with even more spectacular lies. The various calamities Todd has embroiled himself in are starting to come to a head.