Question: Which star of "Cleopatra" was also in a film that starred Nicol Williamson?

Context paragraphs:
Spawn (film): Spawn is a 1997 American supernatural superhero horror film based on the comic book character of the same name.  Directed and co-written by Mark A.Z. Dippé, the film stars Michael Jai White in the title role, and is the first film to feature an African American actor portraying a major comic book superhero.  "Spawn" depicts the origin story of the title character, beginning with the murder of soldier/assassin Al Simmons.  He is resurrected as Spawn, the reluctant, demonic leader of Hell's army.  He ultimately refuses to lead the army in the war against Heaven and turns away from evil.  The film co-stars John Leguizamo (as The Violator, Al's demonic guide and enemy of the film's antagonist) and Nicol Williamson (as Al's mentor, Cogliostro).  Martin Sheen, Theresa Randle, D. B. Sweeney, Melinda Clarke, and Frank Welker (as the voice of Malebolgia) also star in the film.

Jean Marsh: Jean Lyndsey Torren Marsh, {'1': ", '2': ", '3': ", '4': "} (born 1 July 1934) is an English actress and writer.  Marsh co-created and starred in the ITV series "Upstairs, Downstairs" (1971–75), for which she won the 1975 Emmy Award for Outstanding Lead Actress in a Drama Series for her performance as Rose Buck.  She later reprised the role in the BBC's revival of the series (2010–12).  Marsh also co-created the television series "The House of Eliott" in 1991.  Her film appearances include "Cleopatra" (1963), "Frenzy" (1972), "The Changeling" (1980), "Return to Oz" (1985), "Willow" (1988) and "Monarch" (2000).

Laughter in the Dark (film): Laughter in the Dark (French: La Chambre obscure ) is a 1969 French-British drama film directed by Tony Richardson and starring Nicol Williamson and Anna Karina.  It is based on the novel of the same name by Vladimir Nabokov.  Nicol Williamson was brought in as a very late replacement for Richard Burton, who had already shot several scenes.  The director, Tony Richardson, found Burton's lack of punctuality intolerable.

Rex (musical): Rex is a musical with music by Richard Rodgers, lyrics by Sheldon Harnick and libretto by Sherman Yellen, based on the life of King Henry VIII.  The original production starred Nicol Williamson.

Return to Oz: Return to Oz is a 1985 fantasy adventure film directed and written by Walter Murch, an editor and sound designer, co-written by Gill Dennis and produced by Paul Maslansky.  It stars Nicol Williamson as the Nome King, Jean Marsh as Princess Mombi, Piper Laurie as Aunt Em, Matt Clark as Uncle Henry and introduces Fairuza Balk as Dorothy Gale.  It is loosely based on L. Frank Baum's "Oz" novels, mainly "The Marvelous Land of Oz" (1904) and "Ozma of Oz" (1907), yet is set six months after the events of the first novel, "The Wonderful Wizard of Oz" (1900) took place.  Although it is not a sequel and unrelated to the 1939 Metro-Goldwyn-Mayer film, "The Wizard of Oz", it borrows a few elements of it such as the ruby slippers.

Hamlet (1969 film): Hamlet is a 1969 British film adaptation of Shakespeare's play "Hamlet", starring Nicol Williamson as Prince Hamlet.  It was directed by Tony Richardson and based on his own stage production at the Roundhouse theater in London.  The film also stars Anthony Hopkins as King Claudius, Judy Parfitt as Queen Gertrude, Marianne Faithfull as Ophelia, Mark Dignam as Polonius, Gordon Jackson as Horatio, and Michael Pennington as Laertes.

Sakharov (film): Sakharov is a 1984 American drama film directed by Jack Gold and written by David W. Rintels.  The film stars Jason Robards, Glenda Jackson, Nicol Williamson, Frank Finlay, Michael Bryant and Paul Freeman.  The film premiered on HBO on June 20, 1984.

Robin and Marian: Robin and Marian is a 1976 British-American romantic adventure period film from Columbia Pictures, shot in Panavision and Technicolor, that was directed by Richard Lester and written by James Goldman, based on the legend of Robin Hood.  The film stars Sean Connery as Robin Hood, Audrey Hepburn as Lady Marian, Nicol Williamson as Little John, Robert Shaw as the Sheriff of Nottingham, and Richard Harris as Richard the Lionheart.  It also features comedian Ronnie Barker in a rare film role as Friar Tuck.  "Robin and Marian" was filmed in Zamora, Spain and marked Hepburn's return to the screen after an eight-year absence.

Inadmissible Evidence (film): Inadmissible Evidence is a 1968 British drama film directed by Anthony Page and starring Nicol Williamson, Eleanor Fazan and Jill Bennett.  John Osborne wrote the screenplay, adapting his own 1964 play "Inadmissible Evidence".  Nicol Williamson sings two songs in the film: "Room 504" and "Moonlight Becomes You."

The Hour of the Pig: The Hour of the Pig is a 1993 British/French film by writer/director Leslie Megahey, produced by the BBC.  The film stars Colin Firth, Ian Holm, Donald Pleasence, Nicol Williamson, Jim Carter and Amina Annabi.  It was released in the United States as The Advocate.  The film is usually categorised as a drama, although it could also be classified as a mystery or a black comedy.

Supporting paragraphs: Return to Oz Jean Marsh
Answer: Jean Marsh