Danny Kirrane (Trollied), Dylan Edwards (Pramface), Gwyneth Keyworth (The World's End) and Rose Reynolds (Game Of Thrones) will take on the lead roles, with Sean Bean also set to appear in the show as a version of himself.
The sitcom follows the adventures of lovable Morpheus, who manages a bong shop called Stoned Henge with the help of his sister Sarah. His secret crush is their mate Alison, the quirky girl who runs a tattoo business from the back of their shop. There's also his best friend Kent, who sleeps on the sofa, rent free. Together they've been living in each other's pockets since school and aren't moving anywhere fast.
But Morpheus is a dreamer, and his dreams take the form of his hero Sean Bean, who appears in full medieval garb as his personal spirit guide to help him navigate the rough seas of wasting your twenties.
Sean Bean will play the medieval version of himself, with Danny Kirrane as fantasy fanatic Morpheus, Rose Reynolds as his neurotic sister Sarah, Gwyneth Keyworth as love interest Alison and Dylan Edwards as cocky slacker Kent.
The six-part series is being produced by Phil Bowker (PhoneShop), with Tom Marshall (Chewing Gum) directing.
Of the series, Channel 4 commissioner Liz Lewin says: "We can't wait to bring a bit of Westeros to Wiltshire with the Wasted gang's adventures. Their exploits across the series are hilarious and ludicrous in equal measure - the perfect mix for an E4 audience".