Kate returns to America and Tim puts the flat on the market,hiring Barbara,a cleaner who spends more time making wry comments than actually cleaning. Lee is hopeful to buy the flat himself and tries for a mortgage but ultimately,when he fails, Tim sells it to Lucy, whom Lee liked when she came as a potential tenant, and who turns out to be Tim's sister. Once again Lee finds himself with a resident landlady.

Having told work colleague Guy, whom people believe to be gay, that she is not homophobic and has a gay flat mate, Tim's sister Lucy asks Lee to pretend that he is gay. Guy has his doubts and tests Lee by taking him to a gay club, but Tim is suspicious and Lee explains to him about the pretence. They are overheard by Guy, who is also straight - and starting to date Lucy.

Lee is annoyed that Guy,who is older than Lucy,has more or less moved into the flat,walking about in the nude and sees his chance to prove Guy's lack of worth when he discovers that Guy owns a lap-dancing club. Tim is dating a staid librarian but gets a shock when she proves to be one of the lap-dancers,which leads to their splitting up. Lucy also splits with Guy but gets back with him on the proviso that they take things more slowly.

Lucy is concerned about the age gap between herself and Guy, who has a grown-up daughter, Chloe. Whem Chloe is rushed to hospital Lucy and Guy visit, leaving Chloe's baby with Lee and Tim. Disaster strikes when they think that the child has swallowed a Subbuteo football and they think of ways to retrieve it, though it turns out to have been a false alarm.

In order to impress two arty friends of Lucy, Fliss and Toby, Lee claims to have an Open University degree in Art and a knowledge of the subject. When Barbara tells him about a promising young Polish sculptor, who is bound to be big, Lee persuades Lucy to buy some of his work for an exhibition but nobody buys it as he not popular after all, just somebody for whom Barbara cleans - and then Barbara herself accidentally breaks the sculptures.

Barbara and Lucy encourage Lee to go speed dating as they feel he needs a girl-friend. He meets Daisy,an indecisive hair-dresser and invites her back to the flat for dinner but she dumps him anyway. Tim is forced to take Barbara on a date to show that he regards her as more than the hired help after some tactless words whilst Guy is in Thailand which means Lucy is having frequent long distance calls with him.

Lee and Tim get it into their heads that Guy is a gangster who smuggles diamonds into the country after a suspicious package arrives at the flat though it turns out that he is secretly having an engagement ring made up to propose to Lucy. Lucy and Guy arrive at the airport to go to Sicily on holiday and Guy asks Lucy to marry him but she refuses as she finds him too controlling so he spends the holiday on his own. Lee is not sorry.

Geooffrey and Wendy, Tim and Lucy's parents,arrive to spend Christmas at the flat whilst Tim brings Daisy,now his girlfriend,and Barbara stays on to help with the catering. Lee has bought a murder mystery game which involves dressing up and role play but half-way through Geoffrey and Tim argue and Lee has to persuade Geoffrey to calm down and resume the game in order to identify the murderer.