Image copyright 20th Century Fox Image caption Rami Malek shows off the Mercury strut

Queen biopic Bohemian Rhapsody - already the highest-grossing music biopic of all-time - surpassed $900m (£686m) in worldwide ticket sales on Sunday.

The Oscar-winning film has now made $830m (£633m) internationally and $71m (£55m) from domestic UK audiences.

Its latest surge follows unexpected levels of popularity among Japanese audiences - grossing $144m (£110m).

The film cost distributor Fox a relatively meagre $50m (£30m) to make.

Bohemian Rhapsody charts the rise of Queen and the life of its lead singer Freddie Mercury - played by Rami Malek - through the band's music.

Screen International's box office expert Charles Gant told BBC News the film's takings since its initial November release represent a "phenomenal outcome."

However, he stopped short of suggesting it could break the $1bn barrier as the film has now opened in all major markets, including China, where a heavily censored version was released earlier this year.

Despite dividing critical opinion, the film proved popular with audiences and became a front-runner at awards season.

This culminated in four Oscar wins, including best actor for Rami Malek, who won rave reviews for playing the late singer, alongside two Golden Globe wins.

'Word-of-mouth' key

The ongoing success of Bohemian Rhapsody lies in Queen being a "beloved act" whose "songs have really endured," said Gant.

"On top of that, Freddie Mercury was a really charismatic person and performer."

Image copyright 20th Century Fox Image caption The film's Live Aid sequence is seen by many as a fitting end to the film

The film follows the singer's journeys as he finds acceptance in both his sexuality and confidence on stage - concluding at the band's iconic Live Aid performance.

"Story is conflict, screenwriters always tell us, and there was a strong dramatic conflict at the centre of Freddie's life, as he strove for self-acceptance, and to reconcile the 'Freddies' he presented to his family and the world with the real person.

"In other words, there is a compellingly dramatic story to tell," Gant added.

Bohemian Rhapsody is now Fox's fourth-biggest title behind Avatar, Titanic, and Star Wars: Episode I - The Phantom Menace. Overseas, it is the studio's fifth-best release to date.

The film's figures reflect "good word-of-mouth," he says.

"Strong marketing can open a film; after that, the verdict of audiences is what sustains you."

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