Henry Stafford, Duke of Buckingham, is a Yorkist nobleman during the Wars of the Roses, driven by significant political ambition. Recognizing Richard III's capabilities and seeing an opportunity to advance his own influence, he positions himself as a key supporter, actively working to secure Richard's ascent to the English throne.

He first encounters Richard at a social gathering, becoming intrigued. Learning Richard's secret intersex status, Buckingham responds with acceptance, shifting their relationship from political alliance to romance. Buckingham demonstrates a pragmatic and manipulative nature, skillfully navigating court politics to further their shared objective. He participates in Richard's schemes, including the purge of the Woodville family and the assassination of Richard's brother, George, Duke of Clarence.

Their relationship grows complex when Buckingham impregnates Richard. Richard's subsequent termination of the pregnancy triggers Buckingham's deep resentment, marking a turning point. Feeling betrayed and disillusioned, Buckingham shifts from loyal supporter to antagonist, leading a rebellion against Richard. This rebellion fails, foiled by logistical setbacks including flooded rivers that halt his militia. After hiding in Shropshire, Buckingham is betrayed by a retainer, captured, and executed for treason by beheading without trial. His burial site is uncertain.

Historically married to Katherine Woodville and father to five children, the source material explicitly states this adaptation depicts Buckingham as having no children with his wife, a deliberate deviation focusing the narrative on his political and personal relationship with Richard. Buckingham's arc illustrates a trajectory from ambitious kingmaker to fallen rebel, driven by personal grievance and political miscalculation.