The ever-glamorous and self-indulgent Edina Monsoon (Jennifer Saunders) and Patsy Stone (Joanna Lumley) are now in their 60s; Edina is still running her PR agency in London, which is quickly running out of money and interest. The duo realise that Edina needs a miracle to save her PR company and renew her reputation.In the opening scene, Bubble (Jane Horrocks), Edina's long-suffering personal assistant, wakes up a hungover Edina, who has come home drunk yet again from a fashion event. Edina realises that she signs a deal for an autobiography that day. Edina wakes Patsy up and tells her about her book, and how it will be "made into a film because it's about her life", whilst Patsy self-applies Botox.The company head (Mark Gatiss) rejects Edina's book because it is lazily written and there is little interest in Edina's PR agency. Whilst Patsy is setting up designer Huki Muki's fashion event, Patsy learns that supermodel Kate Moss is changing her PR, and immediately informs Edina. Patsy phones whilst Edina is at a PR meeting with rival PR Claudia Bing (Celia Imrie) and during the phone call with Patsy she accidentally leaves speaker on, leading Claudia to learn of Kate Moss's need for a new PR.Edina and Patsy go to the fashion event with Edina's interracial teenage granddaughter, Jane "Lola" Johnson (Indeyarna Donaldson-Holness), whilst at the same time, Saffron "Saffy" Monsoon (Julia Sawalha), Edina's daughter and Lola's mother, recently divorced from her husband, has a night out with her new boyfriend, Nick (Robert Webb). Edina finds Kate Moss (playing herself) on the balcony that is overlooking the Thames. Edina is aiming speak to Kate, but then Edina notices that Claudia is also there to see Kate, she rushes out to speak to Kate first, and accidentally bumps into her, causing her to fall off the balcony into the Thames.There is hysteria all through the event, as Kate is presumed dead. The media immediately is at the scene to report on Kate's disappearance and supposed death. Edina and Patsy are taken into police custody, along with Lola. Saffy arrives to see the three and see if Lola is okay.The following day, Edina returns home. Patsy arrives angry, since she has been fired from her job, due to her association with Edina and the previous night's events. The pair make up and go back to the Thames to see if they can find Kate, and use Bubble as a searching device in the water. In doing so, they supposedly kill Bubble as well and decide to flee the country before the media firestorm gets worse. They call upon Lola to use her credit card as a source of money. Edina, Patsy and Lola arrive at Cannes, France, while Saffy is desperately trying to find out about Lola's whereabouts back in London. She searches for Edina's friend and stylist, Christopher (Chris Colfer) for information.Meanwhile, in Cannes, Edina and Patsy call upon help from Patsy's ex-lover and billionaire, Charlie (Barry Humphries). After Charlie rejects them, they seek help from Edina's elderly and estranged mother (June Whitfield), who is celebrating the birthday of Eddie's relative, Violet (Wanda Ventham). During this party, they encounter the Richest Woman in the World. In order to attract the Woman to get quick money, Patsy quickly changes her identity to a male alter-ego, "Pat" Stone. The following day, Patsy marries the Rich Woman and Edina and Patsy find the wealth they were looking for, and stay in a high-class hotel, with guests such as Dame Joan Collins and Dame Edna Everage (both appearing as themselves).Meanwhile, Edina and Patsy are seen in public by Emma Bunton who then tells Lulu about their whereabouts. Saffy arrives in Cannes with Nick and immediately heads to the hotel to find Lola. Lola is with Emma who tells Saffy of Edina's whereabouts, even though it is the least of Saffy's concerns. Lulu flies out to Cannes and meets with Bubble, who reveals that Kate just swam off and did not drown in the Thames. Bubble also reveals that she is also a millionaire and owns a massive Cannes pavilion because she has had control of Eddie's accounts for years, and has been embezzling from the company.Lulu reports Edina and Patsy's whereabouts to the police, since her only desire is to destroy Edina for what she has done. The police find Edina and Patsy and chase them through the town, as the duo escapes in a small, three-wheeled, fish-market van. They reach Bubble's pavilion, but the van's brakes fail and they roll backwards and fall into an infinity pool attached to Bubble's house. Saffy arrives at the scene to find Edina and Patsy slowly sinking into the pool, still inside the van. Edina apologises to Saffy for being a careless mother and wishes to drown in the pool, and to finally embrace the fact that she is old and can't run from justice forever. Saffy tells her that she loves her, and Bubble reveals that Kate Moss did not drown in the Thames. After finding this out, Edina immediately gets out of the van, realising she is not guilty.A montage plays of countries celebrating that Kate Moss is still alive and that Edina is now her new PR. Edina's PR agency is renewed, and Kate is in even more demand now that she has been found. The film finishes with Patsy revealing to her rich wife that she isn't actually a man called "Pat" and is really a woman. Her wife reveals that she is actually a man and the film closes with the series's popular theme song, "This Wheel's on Fire" sung by Kylie Minogue.