Even 50 years on from its release, What Ever Happened To Baby Jane? is a strange and uncomfortable watch.

The classic B-movie tells of two rival sisters – a former child star, the titular Baby Jane, who has to look after her wheelchair-bound movie queen sister Blanche, in their isolated home.

But as Jane’s mind begins to warp, she starts to subject her sister to a series of extreme torments.

For movie fans, the film’s creeping black and white terror comes with an extra serving of backstage tension, which playwright Anton Burge has exploited for this two-hander play.

The film’s two ageing stars, Bette Davis and Joan Crawford, had a long antagonism, dating back through the studio system to the start of the talkies.

And like the characters they were playing, they began to take chunks out of each other both offset and on.

“Bette had been a stage actor on the East Coast who went to Hollywood in the early years of the talkies,” says director Bill Alexander. “There was a big demand for actors who were very vocally competent, as a lot of silent movie actors couldn’t make the transition from silent to talkies.

“Joan was from the silent era, she had been a dancer, but she managed to make that transition.

“As Bette says to the audience, ‘I’m a proper actor, I was made on the stage – she’s just a dancer.’”

This rivalry had played out across the years, and found its apotheosis on the shoot – particularly during an infamous and well-documented tit-for-tat battle after Joan was accidentally injured onset.

The backstage story is told by both actresses in a mix of monologues and one-on-one spats from their respective back-to-back dressing rooms, as they prepare for a scene.

Greta Scacchi stars as Davis, while Anita Dobson plays Crawford in this production, which is on tour following a summer run at London’s Soho Theatre.

“It’s been really fascinating as they are both fantastic actors but they are very different personalities, just like Bette and Joan,” says Alexander, who took on the two-strong cast when he joined the production as director.

“Like every actor I have ever worked with, they have slightly different approaches to their work and rehearsing, which was great for the two contrasting characters, who also approach their work in different ways. It all fed into the play.”

As for the research into the real-life divas, the writer Burge proved invaluable.

“He’s read everything that has ever been written about Bette and Joan,” says Alexander.

“He could go on Mastermind and win by answering questions about them!

“We have learned a lot both about them and the Hollywood system they came through.”

Prior to the film, both women had been deemed box office poison – Davis having entered a slump since her Academy Award nomination for The Star in 1952 and Crawford, who first earned the sobriquet back in 1938, suffering a dearth of decent roles after 1954’s Johnny Guitar.

“Bette was 54, Joan was 58, and in terms of the male-dominated studios, with their emphasis on glamour and youth, they were well past their sell-by dates in those sexist times,” says Alexander.

“They both saw this as an opportunity to revive and revitalise their careers, and made a really good job of it.

“The film did have a remarkable success – people saw it as an original and quite scary movie, with two cracking performances. It did revitalise their careers in a way but there weren’t many more parts like that out there.”

Theatre Royal Brighton, New Road, Monday, May 28, to Saturday, June 2

Starts 7.45pm, 2.30pm matinees Thurs and Sat, tickets from £13. Call 0844 8717650

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