Nearly five years after being found guilty of murdering three women he met on the internet, Alan Lane (John Lynch) is back in the headlines as the Court of Appeals has dramatically overturned his convictions. The case goes back to the Old Bailey as new evidence comes to light and the stage is set for a fierce battle between Lane's defence barrister Emma Watts (Julie Walters) and John Mallory (Roger Allam) for the prosecution, And as our twelve jury members, each from very different walks of life, receive their summons, they are unaware that their lives are about to change forever...