Mavis Gary is the ghostwriter for a series of failing teen novels. She is also depressed, an alcoholic, and desperately lonely. We meet Mavis shuffling through her mess of an apartment, guzzling Diet Coke for breakfast, and lazily attending to her small dog, whose friendly, excitable behaviour is a stark contrast to Mavis’s almost comatose movements.

As she struggles with the opening chapter to her latest novel, Mavis receives an email from an old high school boyfriend, Buddy Slade, announcing the birth of his first child. Somewhere in Mavis’s confused mind she interprets this as a sign that they should be reunited, despite the fact that he is happily married and now has a child.

And so, hurriedly packing her bags and hitting the road back to her hometown, Mavis begins her misguided search for happiness.

Young Adult is directed by Jason Reitman, and written by Diablo Cody, but those expecting another Juno will be disappointed, for Young Adult is a downbeat affair with a difficult central character.

Mavis is bitter, childish, a snob, deluded and often downright nasty. But as her plan to win back Buddy begins to unravel, she somehow gains our sympathy, perhaps because everyone has, at some time, experienced similar sensations – a disconnection from our roots, the realisation that we’ve been deluding ourselves (particularly when it comes to  relationships), and the realisation that we’ve been stuck in the past.

The success of Young Adult hinges on the performance of Charlize Theron, and to her credit, she is able to portray Mavis as a mean and selfish character, yet still somehow likeable. There are occasional moments when Mavis appears to see herself truthfully, and we can feel her hurting.

The movie’s other key character is Matt Freehauf, played by Patton Oswalt, As a teenager, Matt was brutally beaten, and still suffers from damage to his legs and penis. After meeting Mavis in a bar on her first night in town, Matt becomes her unlikely confidant and reluctant accomplice. We might wonder why Mavis would seek the company of the geeky Matt, but like her, Matt is an outsider.

Matt is also the only person who can see through Mavis and is not afraid to tell her, something she appears to resent, yet perhaps values.

Of course, Mavis’s attempts to reconnect with Buddy are cringingly awkward, climaxing in an embarrassing confrontation, during which Mavis manages to insult as many people as possible.

So what is Young Adult about? Is it a meditation on the meaning of happiness – the idea that happiness begins by changing how you think, not with what you have or haven’t got? Is it about the inability of some people to learn from their mistakes? Or the inability of some people to see beyond their delusions?

Does Mavis learn anything from her experience? ‘I need to change,’ she declares, and we really hope she does.

Young Adult is more a drama than a comedy, yet there is plenty of harsh humour to savour. But don’t expect another Juno. If anything, this is the ‘Anti-Juno’. It’s a good movie for sure, but you won’t necessarily leave the cinema smiling.