Darling, the critics are right: It is not worth seeing unless you:
In the audience at Tysons Corner was no one under age 45, and there is reason for their absence: b o r i n g.
Really, if you must see it, save your neck and take a pillow. Or, save your cash and take a nap (at home).
Factually, it appears to be accurate for about half the show but about one-third of it occurs in dementia victim Margaret Thatcher's head as she talks with her dead husband, Denis Thatcher, played by Jim Broadbent who does a right jolly good job. (Mrs. Thatcher, 86, is still living.)
By means of mental flashbacks while the prime minister suffers the vagaries of dementia, the movie tells Mrs. Thatcher's life story from later childhood (admirably played by Alexandra Roach) through her reign as the only female (and longest serving? Wikipedia is dark (save the Internet) and I cannot verify) British prime minister in the 20th century.
Actual footage of British riots inflamed by Mrs. Thatcher's "let them eat cake" attitude are included.
What else is there to say?