Sketch is a young carer for her disabled mother and is obsessed with Maxxie. Her schemes to make him fall in love with her endanger the college's production of 'Osama: The Musical' and lead her to lie about the drama teacher molesting her, to get a role in the play. Sketch befriends Michelle after seeing her fail to seduce a hesitant Tony, who now also suffers from erectile dysfunction. Sketch drugs Michelle to take her part in the play as Maxxie's love interest. The two kiss on stage as written, but Maxxie tells Sketch that he felt nothing. She slaps him and bursts into tears on stage. That night, she has sex with his best friend Anwar.^[2]

Sid is in despair. His best friend and role model Tony is a shadow of his former self and Cassie has settled down in Scotland. His dad Mark's overbearing father Alex and unpleasant family come to visit. Mark persuades Sid’s mother Liz to act like they are still together as a show for the visiting family. Sid breaks up with Cassie over a misunderstanding. Mark is victimized by Alex and brother Sandy until he stands up to them, ordering them to leave. He regrets being cruel to Sid, realizing that's how his father always treated him. He dies of an apparent heart attack that night and Sid discovers his body the next morning. Sid can't come to terms with it and leaves him where he's sitting. Sid is unable to tell anyone at school, becoming detached. Tony approaches him, saying people told him they were best friends. They attend a Crystal Castles gig where Sid opens up to Tony about his problems. Tony and Sid go back to Sid's house where Mark's body is still in the chair. Sid asks if this (his father's death and his breakup) is real. Sid calls his mother, then he boards a train.^[3]

The gang, bar Tony, go camping for Michelle's birthday, along with Michelle's new step-sister. After an emotional conversation with Sid about the death of his father, Michelle has sex with him on the beach out of sight of the rest of the group. Later, she opens her only present from the group, a watch from Tony, a note inside said 'you wanted some time, happy birthday'. Anwar meets with Sketch near the campsite, but Maxxie and Michelle catch them having sex. The group grudgingly approves of their relationship. Michelle and Sid go back to his bedroom, as a couple, to have sex again. But Cassie is sitting on Sid's bed, awaiting his return and catches him with Michelle.^[4]

Chris is expelled from college and seeks Jal for advice. The two make a pact, Chris has to start looking for a career whilst Jal has to say 'yes' to things, reverting from her conservative personality. Tony is learning how to swim and tells Chris he is getting everything back. After a string of failed jobs, Chris becomes an estate agent. His newfound confidence and success leads him and Jal to become a couple. They squat in a flat which Chris' estate agency was supposed to sell. Cassie also moves in. Cassie lies to Chris telling him Jal left him. Angie comes into Chris' workplace to buy a house. Chris cheats on Jal with her. Chris and Jal split up. Chris loses his job when his boss discovers him and his friends in the flat. Jal discovers she is pregnant. Chris explains his loneliness to Jal and how she turned his life around and they get back together. Chris moves into Angie's old house.^[5]

At a nightclub, Michelle and Sid reveal they are a couple. Cassie states Tony and she should be a couple to get back at them. Tony laughs off the idea. Tony takes ecstasy and elements of his old personality surface. He confronts Sid and Michelle about their relationship before vomiting in the toilets. He meets a girl (Janet Montgomery) who he later sees at a university open day. She is provocative and outspoken, helping Tony overcome some physical issues he has struggled with. She gets a tattoo and they then have sex in a dormitory. Afterward, Tony goes to the nightclub again and interrupts Sid and Michelle having sex in a toilet. He tells them their relationship is wrong and leaves. Both Sid and Michelle have doubts about their relationship. The episode is a visual metaphor of Jungian psychology. The girl Tony meets could be part of his subconscious mind, indicated by the tattoo she got appearing on him.^[6]

Effy becomes the parent of the house with her dad away and her mother’s depression. Tony is coming to terms with his personality. At Effy’s private school she is tasked with completing her art coursework and mentoring the new girl, Pandora Moon. They become good friends. Sid and Michelle break up. Sid wants to get back with Cassie but she has resorted to promiscuity. Sid does Effy’s art coursework in exchange for Effy getting them back together. Revealing his inner emotions, Sid completes the coursework. Effy buys cannabis and sells it at a nightclub with Pandora and Tony. They find Jake who is tasked with seducing Cassie. He goes round hers and they kiss, Effy photographs this and posts the pictures around Sid. He confronts Cassie and the two argue. Sid states she was not there for him when his dad died. He confesses he always loved her and they get back together. Michelle tells Tony she loves him.^[7]

Jal attempts to tell Chris she is pregnant but considers having an abortion. Examinations are approaching. Jal’s dad wants Jal to concentrate on exams and dump Chris. Meanwhile Chris has rented a house with Cassie, and wants Jal to move in. Michelle is embroiled in Spanish revision so Jal tells her she is pregnant in Spanish. Michelle does not understand and instead walks off with her boyfriend, Tony. Jal tells her family she is pregnant. Her father demands she acts quickly. Jal’s mother makes a surprise return to instruct Jal to have an abortion. Cassie finds out Jal is pregnant and suggests she tells Chris. Jal attends her music audition. She goes to Chris’ to confess her pregnancy but Cassie is there and informs Jal that Chris has been rushed to hospital. The nurse tells Jal Chris is going into surgery because there is a blood clot on his brain.^[8]

Chris is discharged from hospital and is recovering, and Cassie sits her philosophy exam. Afterward, Sid cooks a meal for Cassie to celebrate end of exams, but foolishly invites Tony and Michelle, as well as Jal. Due to Michelle and Cassie's rift, the meal is a disaster, and results in Michelle saying Jal is the worst off, inadvertently revealing Jal's pregnancy to Chris, who is distraught. Cassie sees Chris’ mother outside and invites her in but she walks off, crying as she remembers Chris's brother's death. Cassie overhears Chris crying in his bedroom, and he later becomes ill again, forgets Jal’s name and has a blood pressure build up on the membrane, dying in Cassie’s arms. Distraught, Cassie flees to New York, homeless, penniless and with her mental state nearly as bad as ever. Fortunately, she is taken in by a kind waiter from Iowa, named Adam (Stephen Michael Kane), with whom she develops a platonic friendship. Cassie goes to bed one night at Adam's apartment, and wakes up to find a green apple and a note from Adam saying that he 'went away' for a while. This has been interpreted in different ways: many believe that Adam kills himself because of the death of the girl in his pictures, others believe that he runs away to find this same girl. Whatever the case, this leaves Cassie distraught and the episode ends with Cassie running through the streets of New York.^[9]

It is the day of the A-Level results and Chris’ funeral. The gang decide to open the results after the funeral. Chris’ dad visits Sid to tell him that they aren't invited to the funeral. Sid informs Tony of this. They decide to steal the coffin and make the gang say their final goodbyes and then return it. Jal admits to Michelle she had an abortion. Jal begs Sid and Tony to return the coffin. The gang converge on a hilltop overlooking the graveyard and Jal makes an emotional speech. They read out their results to each other that night. Maxxie and his boyfriend leave for London and take Anwar with them leaving a devastated Sketch. Tony and Michelle emotionally decide to stay together for university. Tony buys Sid tickets to New York where he goes to find Cassie. He is last shown outside the diner where Cassie works, their backs turned to each other. The series finishes with Effy in Tony's bed under his duvet cover smiling suggestively at the camera, breaking the fourth wall.^[10]