Black Books centres around the foul tempered and wildly eccentric bookshop owner Bernard Black. Bernard’s devotion to the twin pleasures of drunkenness and wilful antagonism deepens and enriches both his life and that of Manny, his assistant. Bearded, sweet and good, Manny is everything that Bernard isn’t and is punished by Bernard relentlessly just for the crime of existing. They depend on each other for meaning as Fran, their oldest friend, depends on them for distraction. Black Books is a haven of books, wine and conversation, the only threat to the group’s peace and prosperity is their own limitless stupidity.
When Manny defects to Goliath Books after an "incident" with Bernard, his ex-employer's life spirals out of control. Meanwhile Fran returns from holiday only to be greeted by the squalor of Bernard's shop.
When Bernard holds a children's themed book day in the shop, Fran bets Manni and Bernard they couldn't write a children's book over a weekend, while Bernard bets Fran back that she will have an awful time at her friend's hen party.
Manny's parents visit the shop for the weekend, and the lies he's told them throw Fran and Bernard's lives into chaos.
Bernard becomes addicted to gambling and forces Manny and Fran to compete for one job at the shop in order to finance his bets.
Fran & Manny become enamored with a dashing travel writer giving a talk at the shop, while Bernard contends with a most unorthodox new landlord.
Manny and Fran drag Bernard along with them to a party, but the drunken aftermath dredges up secrets and bitterness.