Glenda Jackson has died at the age of 87, after a brief illness, according to her agent, Lionel Larner.

"One of the world's greatest actresses has died, and one of my best friends has died as well," he told NPR. Jackson died Thursday morning at her home in London, he said.

In addition to a distinguished career that included Oscar, Tony and Emmy awards, Jackson represented her London district as a member of Parliament's House of Commons for 23 years.

Jackson lived her life in three distinct acts. The first, and longest act, was as one of the finest actors of her generation. She blazed hot on the stage, first attracting notice in 1964 with the Royal Shakespeare Company when she played Charlotte Corday in Peter Brook's production of Marat/Sade, set in a mental hospital. (She reprised her role in the 1967 film.)

Jackson's success on stage translated to film. She starred in Ken Russell's 1969 adaptation of the D.H. Lawrence novel, Women in Love and the romantic comedy, A Touch of Class, with George Segal. She won Academy Awards for both films. Other roles included Sunday Bloody Sunday and Mary, Queen of Scots. Jackson also entered peoples' households as Queen Elizabeth I in the BBC series, Elizabeth R., for which she won two Emmys.

Quite a trajectory for a woman who grew up among the working-class poor, outside of Liverpool, in a flat with an outdoor toilet. Jackson found her calling acting with an amateur group, and ended up with a scholarship to the Royal Academy of Dramatic Art.

"You learnt that you are your instrument, which is your voice and your shape and how you move," Jackson told Colin Grimshaw in a 1976 interview. "And that can be tuned and toned and kept in trim, ready to actually tackle acting, which is a mysterious process."

New York University theater professor Laurence Maslon said Jackson was a working-class, female version of such British contemporaries as Albert Finney, Michael Caine and Alan Bates. "They were the angry young men, but she was sort of the angry young woman, I suppose," he said. "She certainly had the looks and the skill to transition into film pretty quickly."

But despite great screen and stage success – she starred in Eugene O'Neill's five-hour play, Strange Interlude, in London and on Broadway – Jackson admitted that her profession had its insecurities.

"I think the longer you act, the more you realize you don't know," Jackson told Grimshaw. "The possibilities for making the wrong choices are much greater than the probabilities of making the right ones. And that sort of fear is something that you probably learn to control better, but it doesn't grow any less."

As she was settling into middle age, Jackson was already thinking about her second act. "Certainly, the life of an actress in films is very short. And in the theater, there's a terrible trough when there are no parts worth playing," Jackson explained. "I mean, until you sort of hit about 60 and then a few sort of cracking character parts. And I really can't see myself hanging around for 20 years waiting to play an old biddy in something."

Always a supporter of the Labour Party, Jackson ran for Parliament in 1992 and won. When she stepped down, after serving for more than two decades, she told NPR in 2018, "I enjoyed the constituency responsibilities. I was extremely fortunate. But I must be honest, I don't miss Parliament itself. I mean, I saw egos going up and down those corridors that would not be tolerated for 30 seconds in a professional theater."

But in a moment of political theater, when Prime Minister Margaret Thatcher was eulogized in Parliament in 2013, Jackson took the moment to vociferously criticize her and got roundly booed by Tories on the back bench.

Glenda Jackson's third act was her triumphant return to acting, in her 80s. She starred in Elizabeth is Missing, a television film about woman coping with dementia, as King Lear in both London and New York, and in Edward Albee's Three Tall Women, for which she won a Tony Award in 2018.

When asked about retirement in a 2019 interview on WHYY's Fresh Air, Jackson replied, "Well, if I don't get offered to work, then I'll be retired... I've had a good run."

"I like gardening and I'm a grandma, so I get grandma duty, which is an interesting experience," the legend of British theatre added.