Ian McKellen is set to return to work on his film The Critic once he has recovered from his stage fall.

The Lord of the Rings actor, who injured his neck and wrist when he fell from a stage in June, is gearing up to do some last-minute "danger free" post-production voice work on his murder mystery movie.

The period film, in which he plays a feared theatre critic, debuted to mixed reviews at the Toronto International Film Festival in September 2023 so is being reworked ahead of its general release in the U.K. and Ireland on 13 September.

Screenwriter Patrick Marber has been writing new lines for McKellen, 85, to deliver in a London recording studio as part of the restructuring process in the next few weeks.

"(I'm) literally writing some ADR (Automated Dialogue Replacement) lines and VO (voiceover) as we speak, so we haven't delivered it yet, but it will be fully in the can within the next three weeks, ready for release," Marber told Deadline.

"Once the pen touches paper, Ian will get a call. We will give him peace until it's written. It'll be done in the next two or three weeks. It's danger free and Ian's fine to do it."

McKellen was forced to drop out of the remaining performances of his play, Player Kings, so he could recover from the fall. His understudy David Semark stepped in to play Sir John Falstaff for the remaining London dates and the ongoing U.K. tour.

In The Critic, the veteran actor plays Jimmy Erskine, who becomes entangled in a whodunnit with an actress and a newspaper editor, portrayed by Gemma Arterton and Mark Strong.

Explaining how the film has changed since its festival debut, Marber told the publication, "It's been massively re-edited and revised since Toronto. And now, I think it's really great. McKellen's giving an incredible performance, and Gemma's being brilliant. It's funny, and it's very dark, and I hope it will have some good life out there."