Question: Who plays the primary antagonist in Kenneth Branagh's adaptation of Hamlet?

full_context: Document 1: Edmund (King Lear): Edmund or Edmond is a fictional character and the main antagonist in William Shakespeare's "King Lear". He is the illegitimate son of the Earl of Gloucester, and the younger brother of Edgar, the Earl's legitimate son. Early on in the play, Edmund resolves to get rid of his brother, then his father, and become Earl in his own right. He later flirts with both Goneril and Regan and attempts to play them off against each other.
Document 2: Fortinbras: Fortinbras is either of two minor fictional characters from William Shakespeare's tragedy "Hamlet". The more notable is a Norwegian crown prince with a few brief scenes in the play, who delivers the final lines that represent a hopeful future for the monarchy of Denmark and its subjects. Fortinbras is also the name of the former king of Norway and father of the crown prince Fortinbras. King Fortinbras was slain in the play's antecedent action in battle with King Hamlet. The battle between the two is described by Horatio in Act One, Scene One (I,i) of the play.
Document 3: Hamlet (1996 film): Hamlet is a 1996 film adaptation of William Shakespeare's play "Hamlet", adapted for the screen and directed by Kenneth Branagh, who also stars in the titular role as Prince Hamlet. The film also features Derek Jacobi as King Claudius, Julie Christie as Queen Gertrude, Kate Winslet as Ophelia, Michael Maloney as Laertes, Richard Briers as Polonius, and Nicholas Farrell as Horatio. Other notable appearances include Robin Williams, Gérard Depardieu, Jack Lemmon, Billy Crystal, Rufus Sewell, Charlton Heston, Richard Attenborough, Judi Dench, John Gielgud and Ken Dodd.
Document 4: King Claudius: King Claudius is a fictional character and the primary antagonist of William Shakespeare's tragedy "Hamlet". He is the brother to King Hamlet, second husband to Gertrude and uncle and later stepfather to Hamlet. He obtained the throne of Denmark by murdering his own brother with poison and then marrying the late king's widow. He is loosely based on the Jutish chieftain Feng who appears in "Chronicon Lethrense" and in Saxo Grammaticus' "Gesta Danorum". There had never been an actual Danish King of that name.
Document 5: Hamlet (1948 film): Hamlet is a 1948 British film adaptation of William Shakespeare's play "Hamlet", adapted and directed by and starring Sir Laurence Olivier. "Hamlet" was Olivier's second film as director, and also the second of the three Shakespeare films that he directed (the 1936 "As You Like It" had starred Olivier, but had been directed by Paul Czinner). "Hamlet" was the first British film to win the Academy Award for Best Picture. It is also the first sound film of the play in English. A 1935 sound film adaptation, "Khoon Ka Khoon", had been made in India and filmed in the Urdu language.
Document 6: Hamlet on screen: Over fifty films of William Shakespeare's "Hamlet" have been made since 1900. Seven post-war "Hamlet" films have had a theatrical release: Laurence Olivier's "Hamlet" of 1948; Grigori Kozintsev's 1964 Russian adaptation; a film of the John Gielgud-directed 1964 Broadway production, "Richard Burton's Hamlet", which played limited engagements that same year; Tony Richardson's 1969 version (the first in colour) featuring Nicol Williamson as Hamlet and Anthony Hopkins as Claudius; Franco Zeffirelli's 1990 version starring Mel Gibson; Kenneth Branagh's full-text 1996 version; and Michael Almereyda's 2000 modernisation, starring Ethan Hawke.
Document 7: King Lear (1999 film): King Lear is a 1999 adaptation of William Shakespeare's play of the same name. The film stars Brian Blessed (who also co-directed the film, along with Tony Rotherham) in the title role. Apart from Peter Brook's "King Lear" in 1971, it is the only other feature length film adaptation to preserve Shakespeare's verse. Yvonne Griggs, in "Shakespeare's King Lear: A close study of the relationship between text and film" (2009), characterised it as "a very stilted costume drama".
Document 8: Laertes (Hamlet): Laertes is a character in William Shakespeare's play "Hamlet". His name is taken from the father of Odysseus in Homer's Odyssey. Laertes is the son of Polonius and the brother of Ophelia. In the final scene, he kills Hamlet with a poisoned sword to avenge the deaths of his father and sister, for which he blamed Hamlet. While dying of the same poison, he implicates King Claudius. The Laertes character is thought to be originated by Shakespeare, as there is no equivalent character in any of the known sources for the play.
Document 9: Kenneth Branagh: Sir Kenneth Charles Branagh ( ; born 10 December 1960) is a Northern Irish actor, director, producer, and screenwriter originally from Belfast. Branagh trained at the Royal Academy of Dramatic Art in London, and in 2015 succeeded Richard Attenborough as its President. He has directed or starred in several film adaptations of William Shakespeare's plays, including "Henry V" (1989) (for which he was nominated for the Academy Awards for Best Actor and Best Director), "Much Ado About Nothing" (1993), "Othello" (1995), "Hamlet" (1996) (for which he was nominated for the Academy Award for Best Adapted Screenplay), "Love's Labour's Lost" (2000), and "As You Like It" (2006).
Document 10: Gertrude (Hamlet): In William Shakespeare's play "Hamlet", Gertrude is Hamlet's mother and Queen of Denmark. Her relationship with Hamlet is somewhat turbulent, since he resents her marrying her husband's brother Claudius after he murdered the King (young Hamlet's father, King Hamlet). Gertrude reveals no guilt in her marriage with Claudius after the recent murder of her husband, and Hamlet begins to show signs of jealousy towards Claudius. According to Hamlet, she scarcely mourned her husband's death before marrying Claudius.
Document 11: King Duncan: King Duncan is a fictional character in Shakespeare's "Macbeth." He is the father of two youthful sons (Malcolm and Donalbain), and the victim of a well-plotted regicide in a power grab by his trusted captain Macbeth. The origin of the character lies in a narrative of the historical Donnchad mac Crinain, King of Scots, in Raphael Holinshed's 1587 "The Chronicles of England, Scotland, and Ireland," a history of Britain familiar to Shakespeare and his contemporaries. Unlike Holinshed's incompetent King Duncan (who is credited in the narrative with a "feeble and slothful administration"), Shakespeare's King Duncan is crafted as a sensitive, insightful, and generous father-figure whose murder grieves Scotland and is accounted the cause of turmoil in the natural world.
Document 12: Rosencrantz and Guildenstern: Rosencrantz and Guildenstern are characters in William Shakespeare's tragedy "Hamlet". They are childhood friends of Hamlet, summoned by King Claudius to distract the prince from his apparent madness and if possible to ascertain the cause of it. The characters were revived in W. S. Gilbert's satire, "Rosencrantz and Guildenstern", and as the alienated heroes of Tom Stoppard's absurdist play, "Rosencrantz and Guildenstern Are Dead", which was adapted into a film.
Document 13: Literary influence of Hamlet: William Shakespeare's Hamlet is a tragedy, believed to have been written between 1599 and 1601. It tells the story of Hamlet, Prince of Denmark—who takes revenge on the current king (Hamlet's uncle) for killing the previous king (Hamlet's father) and for marrying his father's widow (Hamlet's mother)—and it charts the course of his real or feigned madness. "Hamlet" is the longest play—and Hamlet is the largest part—in the entire Shakespeare canon. Critics say that "Hamlet" "offers the greatest exhibition of Shakespeare's powers".
Document 14: Horatio (Hamlet): Horatio is a character in William Shakespeare's tragedy "Hamlet". Horatio's origins are unknown, although he was present on the battlefield when Hamlet's father defeated 'the ambitious Norway', Fortinbras (the king), and attended Wittenberg University with Prince Hamlet. Horatio is evidently not directly involved in the intrigue at the Danish court; thus, he makes a good foil or sounding board for Prince Hamlet. He is often not identified as any specific court position, but simply as "friend to Hamlet."
Document 15: Henry V (1989 film): Henry V is a 1989 British historical drama film adapted for the screen and directed by Kenneth Branagh, based on William Shakespeare's play of the same name about King Henry V of England. The film stars Branagh in the title role with Paul Scofield, Derek Jacobi, Ian Holm, Emma Thompson, Alec McCowen, Judi Dench, Robbie Coltrane, Brian Blessed, and Christian Bale in supporting roles.
ground_truth: Derek Jacobi