In Runcorn there are two nearby pubs: the Mayhew where friends Janet, Donna, & Louise drink; and the Archer, where friends Jonny & Gaz drink. When Donna mentions to Janet that she's looking for a boyfriend, Janet gets her boyfriend Jonny to persuade Gaz to go on a blind date. Despite the misgivings of Donna and her mother Flo, the date in the Mayhew goes well, even after the attentions of Louise who has got a job there as a barmaid, and Jonny, who tries to put a spoke in the wheel of what he sees as a future of joint couple dates. Donna accompanies Gaz back to his bedsit, but her passion is cooled on discovering what he has stacked in his cupboard.

Gaz hasn't called Donna in the week since their date, to soften her up for an undemanding relationship. The girls are weighing themselves, and Louise finds she weighs more than she did at 14 for the first time since then, and goes on a diet and exercise regime. Donna gives up waiting for Gaz, and goes round to his pad, where her mother phones to invite him round for a meal and to meet the family, including Donna's very forward sister Katie. On Gaz's advice, Jonny is trying to treat Janet mean, to keep her keen, but then goes missing, so everyone has to drop what they're doing and go searching for him.

Donna moves her toothbrush into Gaz's flat, and he reacts badly, thinking it's the first step to moving in completely. Meanwhile, Flo is encouraging Donna to move out of the family home. Louise is getting chatted up by Kev, who, from her description, the other two are convinced is gay - it turns out they are right, and Louise decides to make the best of things by becoming a ‘fag hag'. Janet tries various ways to improve her love life with Jonny, but just makes him suspicious, he thinks that she's been sleeping with a bloke named Pedro, who Gaz made up because he was too drunk to think straight.

Gaz wants to feel more attractive to women, and hones his chat-up techniques, only to be discovered by Donna at a club. Janet accepts an invitation from arty fellow-student Cameron, who doesn't fart, to perform at a student poetry evening, and has to be rescued from her embarrassment by Jonny.

The lads are winding Janet up with the old one about it being impossible for girls to be as funny as boys. Not one to resist a challenge, Janet trawls through her ‘crack-a-joke' books looking for that killer one-liner Jonny, however doesn't find the fact that he has been fantasizing about Louise quite so funny of course, Gas's advice is to say nothing. Janet is driving everyone mad with her stupid jokes and in a bid to shut her up Gas tells her that Jonny loves Louise. A heartbroken Janet summons a meeting with her friends and lets rip with a torrent of abuse. Unoffended but rather amused by this, the group begin to giggle. Janet is so chuffed at being able to make her friends laugh she forgives them all. Walking home Jonny feebly excuses himself from his Louise fixation by telling Janet that it got her over her joke obsession. Janet gets her revenge by admitting she too has kissed Louise but Jonny takes things that one step too far boasting that he touched Louise's boobs too.

The pitter patter of tiny feet may be just around the corner for Janet and Jonny. Janet turns to Donna and Louise for advice. Louise is her usual tactless self in her reaction, ‘Excellent, I have a single mum friend to show off to my friends at University' while Donna heads to the chemist to buy Janet a pregnancy test. But Janet can't muster up a sample so Donna turns to Flo for hints on possible pregnancy symptoms which, according to Flo, include hot flushes and a passion for Guinness. Jonny has not taken the news about possible fatherhood too well, but several beers down the pub and a talking-to from Louise later he decides that parenthood is perfect for him. When Janet finally has the results from her pregnancy test—Is she or isn't she? And just why is Donna taking such an interest in the whole matter—is there something she needs to tell Gaz?