Zac Efron goes back to his High School Musical hairdo as he films in LA

Zac Efron returned to his High School Musical hairdo when he was spotted filming an upcoming project in Los Angeles this week.

The only movie currently listed as being in production on his IMDb page is the thriller Famous, which sees him play opposite Bridgerton actress Phoebe Dynevor .

Based on a novel by Blake Crouch, who also wrote the script, Famous features Zac in a dual role as both a movie star and his crazed fan.

When he surfaced on the set of a mystery project this week, Zac, 37, sported a look that brought back memories of his own early stardom.

In 2006, at the age of 19, Zac became a household name as the popular teenager Troy Bolton in the Disney Channel movie High School Musical - with a hairstyle strikingly similar to the one he had this Tuesday.

Zac ultimately starred in a total of three High School Musical movies, alongside Vanessa Hudgens , Ashley Tisdale and Corbin Bleu.

In recent years, he has tried his hand at darker roles, including serial killer Ted Bundy in the 2019 biopic Extremely Wicked, Shockingly Evil And Vile.

He has also flexed his comedic chops in two films this year, the Peter Farrelly romp Ricky Stanicky and the romance A Family Affair with Nicole Kidman and Joey King.

Last year, he earned widespread praise for playing real-life wrestler Kevon Von Erich in the biopic The Iron Claw, acting alongside Jeremy Allen White and Lily James.

Zac's latest sighting comes three months after he reportedly hospitalized in Ibiza following an 'incident in a swimming pool' at a luxurious villa .

He was allegedly 'found inside the swimming pool by two people working at the villa who pulled him out of the water,' a source told TMZ .

His representative confirmed he was hospitalized as a 'precautionary measure,' but insisted he was 'recovering just fine' after the 'minor' incident.

Zac was reportedly hospitalized on a Friday night and released the next morning - and by that Sunday, he posted an Insta Stories picture of himself lifting weights, writing: 'happy and healthy - thanks for the well wishes.'

Along with Famous, Zac's upcoming projects listed on IMDb include a Disney+ remake of the 1987 Hollywood comedy Three Men And A Baby.

The 1987 version starred Ted Danson, Tom Selleck and Steve Guttenberg as three single men who find themselves having to look after an infant when one of them discovers that he has conceived the child out of wedlock.

Itself based on the 1985 French movie Three Men And A Cradle, the 1980s Hollywood movie emerged as a runaway box office smash.