Question: Gandalf is a fictional character played by English stage and screen actor, Ian McKellen, in what two J.R.R. Tolkien novels turned films?

full_context: Document 1: Ian Holm: Sir Ian Holm CBE (born 12 September 1931) is an English actor known for his stage work and many film roles. He received the 1967 Tony Award for Best Featured Actor for his performance as Lenny in "The Homecoming" and the 1998 Laurence Olivier Award for Best Actor for his performance in the title role of "King Lear". He won the 1981 BAFTA Award for Best Actor in a Supporting Role for his role as athletics trainer Sam Mussabini in "Chariots of Fire", for which he was also nominated for an Academy Award.
Document 2: Patrick Stewart, roles and awards: The following is a list of theatre, film, and television credits for English actor Patrick Stewart. He is known for his roles as Captain Jean-Luc Picard in the "Star Trek: The Next Generation" franchise and as Professor Charles Xavier in the "X-Men" film series. He has also been the voice of Avery Bullock on "American Dad!" since 2005. He won a Grammy Award in 1996 and is also a Tony, Emmy, and Golden Globe nominee.
Document 3: Ian McDiarmid: Ian McDiarmid ( ; born 11 August 1944) is an Olivier and Tony award-winning Scottish character actor and director. He has appeared in 47 films since 1976. Internationally, he is most famous for his role as Palpatine in the "Star Wars" film series.
Document 4: Gandalf: Gandalf is a fictional character and one of the protagonists in J. R. R. Tolkien's novels "The Hobbit" and "The Lord of the Rings". He is a wizard, member of the "Istari" order, as well as leader of the Fellowship of the Ring and the army of the West. In "The Lord of the Rings", he is initially known as Gandalf the Grey, but returns from death as Gandalf the White.
Document 5: Galadriel: Galadriel () is a fictional character created by J.R.R. Tolkien, appearing in his Middle-earth legendarium. She appears in "The Lord of the Rings", "The Silmarillion", and "Unfinished Tales".
Document 6: Michael Gambon: Sir Michael John Gambon {'1': ", '2': ", '3': ", '4': "} (born 19 October 1940) is an Irish-born English actor who has worked in theatre, television and film. Gambon has played the eponymous mystery writer protagonist in the BBC television serial "The Singing Detective", Jules Maigret in the 1990s ITV serial "Maigret", and Professor Albus Dumbledore in the final six "Harry Potter" films after the death of previous actor Richard Harris. He has won four BAFTA TV Awards and three Olivier Awards.
Document 7: Elrond: Elrond Half-elven is a fictional character in J. R. R. Tolkien's Middle-earth legendarium. He is introduced in "The Hobbit", and plays a supporting role in "The Lord of the Rings" and "The Silmarillion".
Document 8: Patrick Stewart: Sir Patrick Stewart {'1': ", '2': ", '3': ", '4': "} (born 13 July 1940) is an English actor whose career has included roles on stage, television, and film in a career spanning almost six decades. He is a multiple time Olivier, Golden Globe, Emmy, Screen Actors Guild and Saturn Award nominee.
Document 9: Glorfindel: Glorfindel () is a fictional character in J.R.R. Tolkien's Middle-earth legendarium. He is introduced in various material relating to the First Age of Middle-earth, including "The Silmarillion". The name is also used for a character in "The Lord of the Rings", which takes place in Middle-earth's Third Age. In late writings, Tolkien works out how the two characters were one and the same, though this is not evident from the published versions of "The Silmarillion" and "The Lord of the Rings".
Document 10: Ian McKellen: Sir Ian Murray McKellen, {'1': ", '2': ", '3': ", '4': "} (born 25 May 1939) is an English actor. He is the recipient of six Laurence Olivier Awards, a Tony Award, a Golden Globe Award, a Screen Actors Guild Award, a BIF Award, two Saturn Awards, four Drama Desk Awards, and two Critics' Choice Awards. He has also received two Oscar nominations, four BAFTA nominations and five Emmy Award nominations.
Document 11: Gandalf (Finnish band): Gandalf was a Finnish melodic death metal band who incorporated elements of traditional hard rock into their sound. Formed in 1993 by drummer (then guitarist) Nalle Österman (later in Shaman, Korpiklaani and Lullacry), guitarist Timo Nyberg and vocalist Jari Hurskainen, with session drummer Mika "Gas Lipstick" Karppinen, who later achieved fame playing with the band HIM. The name Gandalf came from when the founding fans of the band used to refer to Gandalf's guitarist as the guitar wizard, Gandalf (from The Lord of the Rings). Since then, the band decided to call their band Gandalf. Gandalf released both of their full-length albums through Wicked World Records, a subsidiary of Earache Records.
Document 12: J. R. R. Tolkien: John Ronald Reuel Tolkien, ( ; 3 January 1892 – 2 September 1973) was an English writer, poet, philologist, and university professor who is best known as the author of the classic high-fantasy works "The Hobbit", "The Lord of the Rings", and "The Silmarillion".
Document 13: Aragorn: Aragorn II, son of Arathorn is a fictional character from J. R. R. Tolkien's legendarium. He is one of the main protagonists of "The Lord of the Rings". Aragorn was a Ranger of the North, first introduced with the name Strider at Bree, as the Hobbits continued to call him throughout "The Lord of the Rings". He was eventually discovered to be the heir of Isildur and rightful claimant to the thrones of Arnor and Gondor. He was also a confidant of Gandalf and an integral part of the quest to destroy the One Ring and defeat the Dark Lord Sauron.
Document 14: Albus Dumbledore: Professor Albus Percival Wulfric Brian Dumbledore is a fictional character in J. K. Rowling's "Harry Potter" series. For most of the series, he is the headmaster of the wizarding school Hogwarts. As part of his backstory, it is revealed that he is the founder and leader of the Order of the Phoenix, an organisation dedicated to fighting Lord Voldemort.
Document 15: Ian McKellen, roles and awards: Ian McKellen (born 25 May 1939) is an English stage and screen actor. He is the recipient of six Laurence Olivier Awards, a Tony Award, a Golden Globe Award, two Academy Award nominations, four BAFTA nominations and five Emmy Award nominations. McKellen's work spans genres ranging from Shakespearean and modern theatre to popular fantasy and science fiction. His notable film roles include Gandalf in "The Lord of the Rings" and "The Hobbit" trilogies, Magneto in the "X-Men" films, Sir Leigh Teabing in "The Da Vinci Code" (2006), Sherlock Holmes in "Mr. Holmes" (2015) and Cogsworth in "Beauty and the Beast" (2017).
ground_truth: "The Hobbit" and "The Lord of the Rings"