Charlize Theron is "devastated" at having to shave her hair off again.

The 38-year-old actress has been ordered to chop her locks off for the second time - just as her boy crop was finally growing out - in order to film re-shoots of certain scenes for her forthcoming movie Mad Max 4: Fury Road. The South African-born star will have to return to Namibia with her co-stars Tom Hardy and Rosie Huntington-Whiteley to reprise her role as Imperator Furiosa in the post-apocalyptic action flick.

"Charlize really didn't love having a crew cut and was thrilled when it eventually started growing out. It's now at a great, workable length and she has been proud to show it off. However, early audience tests showed cinema-goers weren't too impressed with a few scenes, so the director and writers have re-grouped and made some important changes. Naturally they want everything to be perfect as it's a big-budget movie, Charlize is obviously contractually obliged to go along with any re-workings of the film, and will soon be shaving off her hair once again. She is devastated. It also means a few more gruelling workouts to rehab the athletic physique she had over a year ago," a source said.

The news came as a surprise since filming for Mad Max 4 originally wrapped last December.

The original 1979 movie, famed for launching Mel Gibson's career, was criticized at the time for its graphic scenes of violence.