Percival is a minor character in Transformers: The Last Knight, appearing as one of the Knights of the Round Table in the film's historical prologue. In the year 484, he stands alongside King Arthur and his fellow knights against a Saxon invasion near Camelot, when the British forces face overwhelming odds. During the battle, Percival observes that the Saxons outnumber the Britons one hundred to one and agrees with Gawain that Merlin is a worthless drunk, reflecting the general doubt among the knights about their wizard's usefulness. King Arthur, however, remains confident in Merlin, who ultimately returns with a giant three-headed fire-breathing dragon that swiftly decimates the Saxon forces and secures a British victory. After the battle, Percival joins his companions in a toast to brothers old and brothers new, honoring the alliance formed between the human knights and the Cybertronian knights who aided them. His role in the story is confined to this opening sequence, which establishes the secret historical bond between Camelot and the Transformers that shapes the film's larger plot. Later, in the modern-day portion of the film, the Oxford professor Viviane Wembly initially regards King Arthur's knights, including Percival, as legend rather than historical fact, though the truth of their existence is eventually revealed. Percival's personality is conveyed through his brief appearances: he is pragmatic, openly skeptical of Merlin's reputation, and loyal to Arthur and his comrades, choosing to stand his ground despite being heavily outnumbered. His motivations are those of a sworn knight defending his kingdom against invasion. His notable abilities are those typical of a medieval warrior, demonstrated through his participation in battle, though the film does not focus on individual combat for him. Because his screen time is limited, Percival has no significant developmental arc; he functions as part of the ensemble of Arthurian knights whose pact with the Transformers provides the historical foundation for the story's hidden history.