Ser Waymar Royce is a knight and the youngest son of House Royce, a noble family of the Vale of Arryn. At some point, Waymar goes to the Wall to join the Night's Watch, where he is placed amongst the Rangers due to his noble birth and skill at arms.
Ser Waymar commands a ranging beyond the Wall, accompanied by Gared and Will, to investigate sightings of wildlings close by. Instead, they find Wights and a White Walker. Royce, along with Gared, was brutally killed. Will flees and is eventually executed by Ned Stark for desertion.
In the A Song of Ice and Fire novels, House Royce of Runestone is distantly related to House Stark. He is the third and youngest son of "Bronze" Yohn Royce, and therefore having little chance of inheriting lands or wealth, he joined the Night's Watch. Waymar was fast-tracked to being an officer because of his noble blood. Eighteen-year-old Waymar is a skilled warrior, trained by his castle's master-at-arms, but is untested in battle. He is arrogant and has a tendency to underrate the experience of men longer on the Wall due to their lower birth, but is not completely stupid.
Nonetheless, when the Others - as the White Walkers are known in the novels - appear he bravely attempts to fight one in single combat. However, his sword shatters as soon as it touches the crystal sword of the Other, and he is defeated and killed. When Will surveys the damage and retrieves Royce's shattered sword Royce revives as a wight, his eyes now icy blue, and murders Will.