Joanna Ward plays Jacqueline (‘Jack'), a 13 year old girl with a talent for sprinting. It's Leicester – 1972 – and Jack wants to win the county athletics title. Convinced she is champion material, her PE teacher and coach, Mr Loughborough (John Thomson), piles on the pressure to train hard.

Having to contend with a strained relationship with her single mum, Vivienne (Amanda Mealing) - and fast school friends, Jack discovers the attractions of smoking, boys and sex. She's got her eye on Steven Green, a rather handsome classmate. Vivienne is determined to keep a beady eye on her daughter's new-found interest in matters carnal and is also convinced Jack is about to be offered a cocktail of class A drugs on every street corner.

On a school cross-country run Jack is approached by Spanner, a David Cassidy look-alike who introduces Jack to the delights of getting wasted on cannabis. Meanwhile Jack's best friend Maxine (Jodie Smith) sets her up in a tryst to do the deed with Steven Green and his spotty mate ‘Poor Bastard'. The trio are disturbed by a local policeman. By now determined to throw off her cumbersome virginity, Jack steals a handful of contraceptive pills from her mum's bedside cabinet and finally gets together with Spanner.