Essex, 1983. Meet Vincent Swan, double glazing salesman extraordinaire. Smart, handsome and cocksure, Vincent will stop at nothing to get a sale.His team at Cachet Windows include Fitzpatrick, a smarmy reprobate who can charm the life savings out of anyone, and Lavender, a failed musician whose crippling politeness and moral backbone have a habit of getting in the way of a sale.The two take a bet on whether Fitzpatrick can pull off the ultimate salesman's con, and sell new windows to someone he's recently sold the exact same windows to. Meanwhile, Vincent's attempt to convince an old colleague to join the double glazing business takes an unexpected turn.