This movie explores the turbulent life of the charismatic Mary Stuart (Saoirse Ronan). Queen of France at sixteen and widowed at eighteen, Mary defies pressure to remarry. Instead, she returns to her native Scotland to reclaim her rightful throne. But Scotland and England fall under the rule of the compelling Elizabeth I (Margot Robbie). Each young Queen beholds her "sister" in fear and fascination. Rivals in power and in love, and female regents in a masculine world, the two must decide how to play the game of marriage versus independence. Determined to rule as much more than a figurehead, Mary asserts her claim to the English throne, threatening Elizabeth's sovereignty. Betrayal, rebellion, and conspiracies within each court imperil both thrones - and change the course of history.Mary Stuart's (Saoirse Ronan's) attempt to overthrow her cousin Elizabeth I (Margot Robbie), Queen of England, finds her condemned to years of imprisonment before facing execution.