Nathan Fillion has been cast as Green Lantern in 'Superman: Legacy'.

The 'Guardians of the Galaxy Vol. 3' actor is one of three new stars joining the cast of James Gunn's upcoming blockbuster as he takes on the role of Guy Gardner and his superhero alter ego.

As reported by Vanity Fair magazine, Fillion will be joined by 'Dora and the Lost City of Gold' actress Isabela Merced as Hawkgirl, while 'X-Men: First Class' star Edi Gathegi has been cast as Mister Terrific.

Gunn has taken over DC Studios with fellow chair and CEO Peter Safran, who told the outlet that the overall goal for the franchise is to make all films and shows accessible for fans.

Safran explained: "The good news is, if you've seen nothing that we've done before, you can watch 'Superman: Legacy', you can watch 'Creature Commandos', you can watch 'Peacemaker' season two, and you can watch 'Blue Beetle'. All of that.

“We are trying to minimise audience confusion and maximise their enjoyment.”

David Corenswet and Rachel Brosnahan were recently confirmed as the new Superman/Clark Kent and Lois Lane in 'Superman: Legacy', with Gunn at the helm.

He and Safran made the decision after shooting screen tests over the weekend of 17 June, with Nicholas Hoult and Tom Brittney also in contention to play Clark Kent and his alter ego, and Emma Mackey and Phoebe Dynevor shortlisted for the Daily Planet reporter.

'Superman Legacy' is currently scheduled for release on 11 July 2025, with filming expected to take place next year.

Further cast members - including who will play Lex Luthor and The Authority - will be brought in in due course.

Corenswet will be the fourth actor to play Superman on the big screen, following in the footsteps of Christopher Reeve, Brandon Routh, and Henry Cavill.

Cavill had been due to return for 'Superman: Legacy' after reprising the role for a cameo in 'Black Adam', but he announced in December he had been given the "sad news" that plans had changed.