'Barbenheimer' fever took hold in the UK as Christopher Nolan's Oppenheimer and Greta Gerwig's Barbie took Â£30m on their opening box office weekend.
According to the UK Cinema Association, that makes it the most successful weekend for UK cinema-going since 2019.
That year, Disney blockbuster Avengers: Endgame opened with takings of Â£43.7m.
The Vue cinema chain said this weekend marked the second biggest in its history by admissions.
Barbie is now on track to become the biggest film of 2023, ahead of Super Mario Bros.
A more detailed breakdown of the weekend's UK box office figures will be published later on Monday.
Barbie's marketing campaign has been huge - and hugely successful - with debut takings worldwide of $337m (Â£293m).
US and Canada takings were enough to make it the biggest opener of 2023 so far in that region.
The film took an estimated $155m (Â£120m) according to distributor Warner Bros, while Oppenheimer made $93.7m (Â£72m), Universal Pictures said.
The North American box office figure broke the opening weekend record for a female director, easily overtaking the $103.3m opening of Patty Jenkins' Wonder Woman.
Both films have been a welcome relief for cinemas who are battling against the juggernaut of streaming.
Oppenheimer's plot is centred on the development of the first atomic bomb, starring Cillian Murphy and directed by Christopher Nolan.
Barbie tells a coming-of-age story of the children's character where she explores her identity and encourages friend Ken to establish individuality.
According to Billboard, film polling service PostTrak reported that women made up 65% of the Barbie audience, while 40% of ticket-buyers were under the age of 25.
It wasn't all plain sailing for Barbie, however. In China, the world's second biggest movie market, the film opened in fifth place.
It took just $8.2 million in its opening three days, according to data from consultancy firm Artisan Gateway, although it's not unusual for Chinese audiences to favour homegrown cinema over Hollywood and some analysts considered that hitting the $8m mark was above expectations.
Meanwhile, Indian cinemagoers were in for a surprise at one screening of Nolan's film, which was reportedly accompanied by Barbie subtitles.
"Friend of my cousin posted on insta that a cinema played Oppenheimer with Barbie subtitles," wrote Twitter user Sapun.
Barbie's release was delayed in Pakistan's Punjab province on Friday over "objectionable content", officials said.