Tim is a single father trying to win back the respect and affections of his precocious nine year old son, Marcus. In the hope of proving that he is not a complete loser, Time quits his dead-end job but his life changes forever when he is accidentally recruited as a trainee spy for MI5. Supervising Tim at work is irrepressible MI5 boss, The Examiner, who teaches the recruits his own unorthodox approach to the espionage game. Adding to the chaos of Tim's life are his acidic ex-wife Judith, her enthusiastic new boyfriend Philip, their obsessive family therapist and his anti-social best friend Chris. And is there romance on the cards with fellow agent Caitlin?

Now a fully licensed MI5 agent under the eccentric eye of The Examiner, Tim is still raw from the disappointment of Caitlin's fiancé turning up unexpectedly and so he sets about trying to sabotage their relationship with the help of best friend Chris. Meanwhile, Marcus starts a new school term only to discover that his status as top dog is under threat from new boy Nick. And the family has to deal with a new therapist, Owen, whose unorthodox methods give Philip cause for concern when he realises that Owen is trying to seduce Judith.