The entire plot of Braveheart hinges on a series of escalating tragedies and betrayals that culminate in martyrdom. The key event that sparks the rebellion is the public execution of Wallace's wife, Murron, by an English sheriff after she resists assault. This transforms Wallace's personal desire for a peaceful life into a burning quest for vengeance that quickly morphs into a national uprising.
A major plot twist occurs at the Battle of Falkirk. After being initially successful, Wallace's army is defeated because the Scottish nobles, having been bribed by King Edward, withdraw their forces. The most devastating blow is the revelation that a mysterious knight fighting for the English is none other than Robert the Bruce, the man Wallace hoped would lead them. This betrayal breaks Wallace, not physically, but spiritually, leading him into a period of guerrilla warfare.
The final, ultimate betrayal leads to Wallace's capture. He is lured to a meeting in Edinburgh by the Scottish nobles, only to be seized by English soldiers. It is revealed that Robert the Bruce's father conspired with the other nobles to hand Wallace over. During his brutal public execution in London, Wallace refuses to submit or beg for mercy, instead using his last breath to shout 'Freedom!'. The film reveals a final hidden meaning in its closing moments: Princess Isabelle, visiting the dying King Edward, whispers to him that she is pregnant with Wallace's child, meaning the king's bloodline will end and Wallace's will endure, in a sense, through the future royalty of England. The film concludes years later at the Battle of Bannockburn, where the guilt-ridden and inspired Robert the Bruce finally takes up Wallace's mantle, invokes his name, and leads the Scots to decisively win their freedom.