Career: Determined to become a serious actor, Grammer spent two years at New York's Juilliard School. He then worked in theatre before making his TV debut in 1983 miniseries Kennedy. He had a stint in soap Another World, and in 1984 began playing Dr Frasier Crane in Cheers. After Cheers ended in 1993, he launched the hugely popular spin-off series Frasier. In addition to starring in 264 editions of the sitcom, he directed more than 30 episodes. Grammer has also starred in X-Men: The Last Stand, short-lived sitcoms Back to You and Hank, and the dramas Boss and Partners. He is also the voice of Sideshow Bob in The Simpsons.

Career: David worked steadily on the stage throughout the 1980s and made his film debut in Bright Lights, Big City in 1988. He was later offered a role in Little Man Tate by former Yale classmate Jodie Foster, who remembered him from a student play. In 1992, he was in short-lived sitcom The Powers That Be and caught the eye of Frasier's creators, who noticed his resemblance to Kelsey Grammer and wrote the role of Niles especially for him. His performance in the long-running sitcom earned him four Emmy awards and a reported salary of $1million per episode for the last few seasons. Frasier came to an end in 2003 and David has since been seen in the film Down With Love and in various stage productions on Broadway and the West End. He won a Tony Award in 2007 for his performance in Kander and Ebb musical Curtains.

Career: After moving to Los Angeles, Leeves appeared in a series called Throb and made guest appearances in a number of shows, including Seinfeld and the miniseries Pandora's Clock. Her big break came in 1993 when she was cast as Daphne Moon in Cheers spin-off Frasier. Leeves has starred on Broadway as Sally Bowles in Cabaret and played parts in a variety of films, including Monty Python's The Meaning of Life (1983), To Live and Die in LA (1985), Miracle on 34th Street (1994) and Music of the Heart (1999). Since 2010, she has starred in the sitcom Hot in Cleveland.

Career: In the US, Gilpin struggled to get decent roles, so worked as a make-up artist and radio producer. Later, she became an apprentice at the acclaimed Williamstown Theatre Festival, and had small parts in TV shows Cheers, Matlock, 21 Jump Street and Wings. Actress Blythe Danner liked her work and helped her gain roles, although the Frasier job only came about when original choice Lisa Kudrow (of Friends) dropped out. Gilpin's other projects include How to Kill Your Neighbour's Dog and Final Fantasy: The Spirits Within. She also runs production company Bristol Cities with former Frasier co-star Jane Leeves. Since Frasier ended in 2004, Gilpin has appeared in Medium, Desperate Housewives, Law & Order: Criminal Intent, Make It or Break It, and Hot in Cleveland.

Career: Castellaneta started working at The Second City, an improvisational comedy theatre, in 1983 and stayed until 1987. During this time, he did voiceover work for various radio stations. He was hired to work on The Tracey Ullman Show and he started voicing Homer Simpson in The Simpsons, which was initially aired as a series of animated shorts. The Simpsons has since become a half-hour show and Castellaneta has continued to provide the voice of Homer. He has also voiced many other characters, including Grampa Simpson, Barney Gumble and Krusty the Clown. Castellaneta and his wife, Deb Lacusta, have also written several episodes of The Simpsons. He has done voice acting for a number of other animated series too, including Back to the Future, Aladdin, Earthworm Jim, Hey Arnold!, The Batman and Futurama. Besides voice acting, Castellaneta has had on screen parts in such series as Entourage, Everybody Loves Raymond, Friends, Greek, Parks and Recreation, How I Met Your Mother and Desperate Housewives. He has appeared in such films as K-9 (1989), The War of the Roses (1989), The Pursuit of Happyness (2006), Super 8 (2011) and Fantastic Four (2015).