In 1306, the delicate peace in Scotland is disrupted as Robert the Bruce (Angus Macfadyen) and John Comyn engage in a covert meeting within a chapel, a gathering fraught with betrayal. Comyn proposes a fateful bargain: relinquish his claim to the Scottish throne in return for land and riches. However, Robert is aware of Comyn's malicious intentions to betray him to the English, which ignites a fierce and deadly retaliation. The chaos that unfolds is spearheaded by James Douglas (Diarmaid Murtagh), Robert's devoted vassal, as they square off against the guards outside in a brutal clash.
As winter falls in 1313, a sense of desolation blankets Robert and his small band of loyal men, encamped in the depths of the woods. It is in this grim setting that Douglas shares his unwavering belief with a young boy named Hamish, affirming that their leader will never yield and will undoubtedly guide them to triumph. Yet, Robert's tone is laced with heaviness as he declares an end to their war and commands his comrades to return to safety. Meanwhile, three disgruntled soldiers hatch a scheme to capture Robert and claim the bounty on his head, dismissing their oaths. One soldier, a philosopher among them, cautions that taking their leader's life would be a heinous act.
As Robert departs, flanked by Hamish and Douglas, murmurs of discontent echo among those questioning his dedication. Morag Macfie (Anna Hutchison) stokes the embers of resentment in her son Scot (Gabriel Bateman), deepening his hatred towards Robert—who had the audacity to traverse the woods without addressing them. This animosity stems from the anguish of losing his father, a valiant warrior who fought alongside Robert. Morag and Scot make their somber pilgrimage to his grave, where the boy opens up to his mother about his feelings regarding this missed encounter.
The three deserters eventually track down Robert, unleashing a vicious assault that results in him sustaining grave wounds inflicted by Will (Patrick Fugit). Though he escapes and finds refuge in a nearby cave, Robert is beset by feelings of despair as he witnesses a spider persistently weaving its web, succeeding after numerous attempts—symbolic of his own faltering quest to liberate Scotland, steeped deeply in folklore. Meanwhile, Will attempts to claim the bounty by rallying soldiers, including the devious Sheriff Brandubh (Zach McGowan), to the scene. In a shocking twist, Brandubh executes Will and masks the truth with a facade of friendship as he sets out to hunt for Robert.
In a blacksmith shop, Carney (Brandon Lessard), Scot's nephew, repairs Robert's sword and has a fleeting encounter with Briana, the daughter of Sean the blacksmith. In a fortuitous turn of events, Morag's home becomes a refuge for the injured leader, thanks to her sons, Scot and Carney, who bring him back despite their clan’s alignment with the English. As winter transitions into spring, Robert finds a semblance of comfort amidst Morag's family. He conveys a heartfelt apology to Scot for the loss of his father and shares his martial knowledge with Carney, forming a deep bond with Morag during their time together. Nonetheless, Robert remains fiercely committed to continuing the fight for a righteous cause, driven by the belief that the sacrifices made by families like Morag's must not be in vain.
One consequential evening, a loyal follower of Brandubh inadvertently discovers Robert's location within Morag's dwelling and rushes back to relay the information to his leader. Seizing this opportunity, Brandubh plots a surprise attack, but Briana, ever alert, overhears and promptly warns Morag's family. Swift preparations for battle ensue, with Iver and Scot taking their positions among the trees, armed with bows, while Carney stealthily conceals his sword in the shadows. Briana finds solace in the nearby barn, preparing for the storm that is about to unfold.
The conflict erupts as Brandubh leads his men into Morag's home, launching a vicious attack that leaves Morag badly wounded. Robert steps forward, asserting his claim as the King of Scotland and declares his protective authority over Morag's family. A fierce skirmish ensues, where Robert, Carney, Scot, Iver, and Briana rally together to fend off Brandubh's forces. Despite their limited numbers, they emerge victorious, but not without the heart-wrenching loss of Briana.
In the aftermath, Morag selflessly acts to save Robert's life, striking down Brandubh during the fray. As they carry Briana to her final resting place, Robert escorts Morag's family to the secure fortress of Angus MacDonald, where they are received with open arms. Years later, a grieving Morag stands at Scot's grave, a poignant reminder of his sacrifice in the Battle of Bannockburn in 1314, a pivotal moment that would ultimately forge Scotland's freedom.
