The Lion in Winter is a historical drama set in 1183 AD, during a Christmas family gathering at King Henry II's palace in Chinon, France. The King is an aging monarch who has been ruling England for over three decades. He has three sons, Richard, Geoffrey, and John, all of whom want to inherit the throne but he refuses to commit to any of them, instead favoring his mistress Alais, who is also his son Richard's fiancée.
The film opens with Henry II returning from France, where he has been embroiled in a long-standing conflict with King Philip II of France. He is accompanied by his estranged wife, Queen Eleanor of Aquitaine, who has been held prisoner by him for the past ten years. The King's three sons, Richard, Geoffrey, and John, also arrive at the palace along with their respective entourages.
As the family members gather for the Christmas celebration, it quickly becomes apparent that all is not well. Queen Eleanor and her three sons have their own agendas, and they begin to plot against each other to secure the throne. Queen Eleanor sides with Richard, whom she believes is the most capable of ruling England, while Geoffrey aligns with his father, hoping to gain his favor. The youngest son, John, is mostly ignored by everyone and is seen as weak and indecisive.
The rest of the film is a game of cat and mouse, as the family members engage in verbal battles, elaborate schemes, and political maneuverings to outwit each other. The King and his sons play a dangerous political game, each trying to gain the upper hand over the others. Meanwhile, Alais, caught between her love for Richard and her loyalty to the King, becomes a pawn in their power struggle.
In the end, King Henry II finally decides to name John as his successor, much to the disappointment of his sons and ex-wife. However, in a dramatic turn of events, Richard challenges his father's decision and a battle ensues between the father and son. Although Richard emerges victorious, his father sees through his manipulations, and the film ends with a bitter conclusion as the family members leave the palace, each uncertain of their fate.
