Taking on what has been described as one of the greatest roles in musical theatre must come with a certain amount of expectation and pressure, but Imelda Staunton is taking it in her stride.

The Olivier and BAFTA award-winner, most recognisable as Professor Dolores Umbridge in the Harry Potter films, would rather focus on getting under the skin of Mama Rose, the central character in Steven Sondheim’s musical Gypsy, which comes to Chichester Festival Theatre this month.

“When an opportunity comes to get your mind, and voice and heart around a piece like this, it is very rewarding.

“It is a responsibility,” says Imelda. “But I want to get rid of that, because I don’t need that pressure on top of everything else.”

Based on the memoirs of Gypsy Rose Lee, the story centres on Rose Hovick, who has big plans for her two daughters and their family vaudeville show, which tours small-town America.

However, things begin to unravel when her teenage daughter June quits the show, leading Rose to turn her attention to her shyer daughter Louise.

“She’s a survivor and a fighter, and wants success for her children and herself and will stop at nothing to get it,” says Imelda. “She is driven by a constant need for success and stardom.

“I would say she’s pretty dysfunctional.”

The 1959 hit Broadway musical has not been performed in the West End in more than 30 years, and there has been speculation over whether it will return London next.

“I don’t know why it hasn’t been done here for so long,” says Imelda. “It’s a good play without the songs, then you have these really great songs.”

Among these are classics such as Let Me Entertain You, Rose’s Turn and Everything's Coming Up Roses.

The themes are more relevant today than ever in a world where reality television rules and fame is a goal in itself, says Imelda.

“Apparently, the most important thing is fame, and that’s pretty sad I think – I mean fame in a showbiz way.

“It’s that relentless ‘anyone can be whatever they want to be’, but the truth is they can’t.

“Rose is the kind of woman who fights and works for what she has got.

“She isn’t asking for someone to make it happen for her.”

Imelda grew up in North London and graduated from the Royal Academy of Dramatic Art (RADA) in 1976, since which time the actress has notched up an impressive roll of theatre, television and film performances.

This is Imelda’s second starring role in a Sondheim musical, following her portrayal of Mrs Lovett in Sweeney Todd in 2011, a performance which saw her pick up the Olivier Award for Best Actress in a Musical.

“What I love about Gypsy is that it is very moving and very entertaining,” says Imelda. “You have got all these layers and then this very complex story.

“I think people may see themselves in Rose, or think ‘that’s not the way to do things’, to live your life through your children.”

It was while she was working on Sweeney Todd, directed by Jonathan Kent, that she signed up to Gypsy, also directed by Kent.

Her character in Sweeney Todd, Mrs Lovett, is the accomplice of the barber/serial killer.

Known as a character actress, one of Imelda’s most celebrated roles was as Vera Drake in the Mike Leigh film of the same name, which tells the story of another working class woman, one who performs illegal abortions in 1950s London.

For this performance she was Oscar-nominated and won BAFTA and Venice Film Festival awards for Best Actress.

Her television credits include Psychoville and Cranford, while her other film roles include Maleficent and, most recently, Pride, the true story of a group of gay activists who decide to support a Welsh mining community during the 1984 strike, in which she plays one of the central characters, Hefina.

Imelda’s previous stage role was in Good People in the West End, also directed by Kent, in which she played Margie, a struggling single mother.

“It is very nice to play strong women – it is to be cherished,” reflects Imelda.

As for what is next in the pipeline, Imelda mentions that she has just recorded a Christmas Victoria Wood television special.

“But I have already done Good People, now Gypsy, and Pride is in the cinemas – I think that’s enough for one year.”

Gypsy director Jonathan Kent will be in conversation with author and broadcaster Kate Mosse on Monday, October 13 at 5.45pm. Tickets are free but advance booking is required.

On October 30, there will be the chance to meet some of the company at a post-show discussion, while an event exploring Gypsy from the inside-out on November 5 will feature technical crew, cast, and creative teams. Tickets are £5, Friends & Concessions £4.

  •  Gypsy will be at Chichester Festival Theatre from October 6 to November 8. For tickets call 01243 781312 or visit www.cft.org.uk