In 2008, an asteroid fragment crashes into Peckham, London, striking Bob, a mild-mannered and socially awkward postman. He suddenly gains abilities that echo Superman, and after an early attempt to figure things out on his own—culminating in a collision with The Shard—he surrenders to the authorities. He is taken in by the Ministry of Defence and, reborn as SuperBob, becomes the world’s first superhero, serving Britain as a civil servant under the government.
Six years on, Bob’s boss Theresa Ford authorizes a documentary project aimed at presenting SuperBob as a normal guy. Bob still lives in Peckham with his security guard Barry and his cleaner Doris, who also works at the care home where Bob’s mother resides as they search for funds to open a nursery in Colombia. The crew explains that Bob takes a day off every Tuesday, and he reveals he’s about to go on his first date in six years with librarian June.
While shopping for clothes with [Doris], Bob receives an urgent call from Theresa summoning him for a meeting about introducing him to American senator Bill Jackson. Jackson is in London for the MOD Weapons Summit and views SuperBob as a dangerous, uncontrollable asset—a narrative fuel for a smear campaign linked to America’s earlier failed bid to recruit Bob. After speaking with June and taking [Doris]’s advice, Bob defies Theresa and heads out on his date. A separate call from the care home interrupts him, as his mother has an accident. Given her short-term memory loss, she mistakenly believes Bob and Doris are dating.
To keep his mother happy, the pair share a tender dance at the home’s celebration, and it’s clear they have growing feelings for each other. June calls, so Bob invites her to dinner at his house. After they leave the care home, Bob hears news of a multi-car pileup and rushes to help, only to be scolded by Theresa for not following orders on his day off. He still disobeys, comforting a fatally injured woman before she dies. Back home, Doris briefly consoles him until June arrives for dinner. When Bob finds a note from Doris mentioning a problem, he admits he would rather be with Doris than pursue the date with June.
The dinner is interrupted when Bob and June are summoned to the MOD for the Weapons Summit. June admits that Theresa blocked their lunch but, though she likes him, Theresa and the MOD want him paired with June because she’s American. Yet, during the handshake with Senator Jackson, Bob learns that the US government has funded a nursery for Doris and is sending her away. Furious at the manipulation, he smashes through the MOD roof and takes off in search of Doris, sparking a worldwide manhunt with sightings across the globe.
In time, Bob locates Doris at the care home, where local residents block the entry to protect them as they openly express their feelings for each other. He convinces her to join him in Colombia to pursue her dream of working with children. He resigns from the MOD and goes freelance, declaring he’s no longer a civil servant or the UK’s property, and he offers his number to help others. He bids farewell to Theresa and his mother, and he and Doris—accompanied by Barry—fly off into the night toward Colombia.
The epilogue shows the couple thriving in Colombia, continuing the superhero work together. Theresa has been reassigned to Afghanistan, and scientists have spent six years examining the meteorite to uncover the source of SuperBob’s powers, but without success.
