The Iron Lady is a 2011 British biographical film based on the life of Margaret Thatcher, the longest serving Prime Minister of the United Kingdom of the 20th century. The film was directed by Phyllida Lloyd. Thatcher is portrayed primarily by Meryl Streep, but also, in her formative and early political years, by Alexandra Roach. Thatcher's husband, Denis Thatcher, is portrayed by Jim Broadbent, and Thatcher's longestserving cabinet member and eventual deputy, Geoffrey Howe, is portrayed by Anthony Head.

'The Iron Lady' is a surprising and intimate portrait of Margaret Thatcher (Meryl Streep), the first and only female Prime Minister of The United Kingdom. One of the 20th century's most famous and influential women, Thatcher came from nowhere to smash through barriers of gender and class to be heard in a male dominated world.

The film begins circa 2008 (opening against the backdrop of news of the Islamabad Marriott Hotel bombing) with an elderly Lady Thatcher buying milk unrecognized by other customers and walking back from the shop alone. Over the course of three days we see her struggle with dementia and with the lack of power that comes with old age, while looking back on defining moments of her personal and professional life, on which she reminisces with her (now dead) husband, Denis Thatcher. She is shown as having difficulty distinguishing between the past and present. A theme throughout the film is the personal price which Thatcher has paid for power. Denis is portrayed as somewhat ambivalent about his wife's rise to power, her son Mark lives in South Africa and is shown as having little contact with his mother, and it is implied that Thatcher's relationship with her daughter Carol is at times strained.

While the film was met with mixed reviews, Streep's performance was widely acclaimed, and considered to be one of the finest of her career. She received her 17th Academy Award nomination and ultimately the Academy Award for Best Actress for her portrayal of Thatcher across four decades. She also earned her third Golden Globe Award for Best Actress –Motion Picture Drama (eighth overall), and her second BAFTA Award for Best Actress in a Leading Role.