Feeling the pressure of trying to fill a rundown London church, the Reverend Adam Smallbone is elated when his congregation quadruples overnight. But the sudden influx of worshippers isn't down to word getting out about his wonderful sermons - there's a rumour going round that the local church school’s about to get a great Ofsted report. Faced with a bunch of hypocritical parents vying to out-Christian one another in the hope he'll recommend their child, Adam is tempted to enter into a deal with the devil and trade a school place for the expensive restoration of a broken stained-glass window.

When the Archdeacon tells Adam his collection plates are too light, salvation appears to come in the form of fellow priest Darren Betts. Darren needs a temporary venue for services whilst his own church is renovated so Adam welcomes Darren and his huge congregation of happy-clappy evangelists with open arms. But the union soon becomes a battle for hearts and minds as Darren refuses to leave Adam's church. There’s tension at home too - Adam's wife Alex is feeling neglected and announces they need to rekindle their love life.

Adam's decision to allow a Muslim children's prayer group to use the church for classes brings his congregation's prejudices to light. Inspired by the clear moral stance he sees in the Islamic classes, Adam decides to take a stand himself and oppose a lapdancing club threatening to open opposite the school. But when he finds himself in one of the branches checking out pole dancers in the name of research, things get rather more complicated.

Adam succumbs to envy when he hears an old rival on Thought for the Day. But his own attempts to make a career of his vocation spectacularly backfire - an ill-advised comment on The One Show about homosexuality within the church results in orders from the Archdeacon to take media instruction from the very vicar Adam was trying to out-do. And while Adam neglects his pastoral duties in favour of climbing the greasy pole Colin looks for meaning outside of St Saviour's, swapping his lager for spliffs to dabble in the Rastafari religion.

Tired of feeling excluded and derided by the rest of society, Adam is thrilled to meet Leon who’s keen to get married at St Saviour's. Leon sees past the dog collar and a friendship develops, with the pair sharing pints in the local pub and even jogging together. But the bromance comes to a crashing halt at an embarrassing vicarage dinner party when Adam discovers that his wife Alex went to college with Leon - and that they had done something naughty in a rather surprising place.

After a terrible review of one of his sermons on a Christian website, Adam has a crisis of faith which, to Alex's surprise, seems more serious than his usual biannual episodes of doubt. While he's at home experimenting with leaving the cloth by sitting in his pants watching daytime telly and gambling on the internet, someone else is going around the parish impersonating a vicar to get free beers and avoid parking tickets. Adam's meltdown comes to a head when he drunkenly comes on to Ellie at a Vicars and Tarts party in aid of the school library - and Alex finally snaps.