Tony Dixon works in an unglamorous backwater of a London bank. Trapped in a job he hates, with a girlfriend he doesn't deserve, he's drinking too much and wondering how to escape. One day a letter arrives which should bring him the freedom he craves. Instead, it leads him into a sordid world of Dark Money, tax-dodging plutocrats, crooked journalists and a foul-mouthed peer of the realm. Can he find redemption and win back the women he loves? All it would take is One Great Thing...