While the show is extremely funny, BoJack Horseman happens to be one of the more dramatic animated series, which has proven to be a large part of the show's draw. Making a show like that means that the characters have to be voiced by actors that not only have great comedic timing but can also handle the more serious emotional beats that the show requires.
Luckily, Netflix was able to get a talented cast of actors, many of which have won or been nominated for awards for their work, to provide the voices for the human and animal characters.
Will Arnet As BoJack
The show follows washed-up horse celebrity, BoJack Horseman, who is attempting to reignite his career after the success of his 90s show Horsin' Around. Despite being the main character he is easily the least likable character on the show and the audience members oftentimes find themselves rooting against him.
BoJack is played by Will Arnet who, in addition to voicing BoJack, also was an executive producer on the show. Arnet is best known for his roles as G.O.B comedy series Arrested Development, a role that earned him an Emmy nomination, and Devon Banks on 30 Rock. He has appeared in a few films like Lego Batman, When in Rome, and the Teenage Mutant Ninja Turtles franchise.
Amy Sedaris As Princess Carolyn
Princess Carolyn is Bojack's ex-girlfriend as well as the former agent and manager of his acting career. She is also one of the show's many animal characters and is a pink Persian cat.
Princess Carolyn is voiced by Amy Sedaris whose first major role was as Jerri Blank in the series Strangers with Candy. Sedaris appeared as Hurshe Heartshe in the series The Heart, She Holler, and as Mimi Kanasis in Unbreakable Kimmy Schmidt. She also stars in At Home with Amy Sedaris, a series she created which earned her two Emmy nominations. Sedaris has also appeared in various movies, including School of Rock, Elf, and Jennifer's Body.
Aaron Paul As Todd
Todd Chavez is BoJack's 20-something human housemate that is constantly finding himself in the middle of all sorts of zany situations. Despite their conflicts, Todd is extremely loyal to BoJack and values their friendship.
Todd is played by Aaron Paul who is widely recognized for his role as Jesse Pinkman on Breaking Bad and in the film El Camino: A Breaking Bad Movie. He has also starred in movies like Need for Speed and Central Intelligence. His most recent roles have been as Eddie Lane on The Path and Caleb Nichols on Westworld.
Alison Brie As Diane
Diane Nguyen was Mr. Peanutbutter's girlfriend that BoJack develops a friendship with as she helps him ghostwrite his autobiography.
Diane was played by Alison Brie roles as Trudy Campbell in Mad Men and Annie Edison in Community, she currently stars as Ruth Wilder on the critically acclaimed Netflix show GLOW. Brie has also starred in films such as How to Be Single, The Disaster Artist, Horse Girl.
Paul F. Tompkins As Mr. Peanutbutter
Mr. Peanutbutter is an overly-optimistic yellow Labrador Retriever friend of BoJack and Diane's boyfriend and later ex-husband. He is also the former star of Mr. Peanutbutter's House, a series strangely similar to Horsin' Around.
Mr. Peanutbutter is played by Paul F. Tompkins who has appeared on several podcasts but is best known for his work on shows like Real Time with Bill Maher, Mr. Show with Bob and David, and Best Week Ever with Paul F. Tompkins. In addition to shows, he has also been in several movies such as The Informant! and There Will Be Blood
Diedrich Bader As Judah
Judah is Princess Carolyn's assistant who works with her at Vigor and later at VIM. He and Princess Carolyn would get married in season 6 after he confessed his love for her.
Judah is played by Diedrich Bader. Bader has appeared as a series regular on The Drew Carey Show, American Housewife, and Veep. His movie roles have been in The Beverly Hillbillies, Office Space, and Napoleon Dynamite. BoJack is not his first time doing voice work with him acting on Batman: The Brave and the Bold as Bruce Wayne and The Grim Adventures of Billy and Mandy as Hoss Delgado, among others.
Aparna Nancherla As Hollyhock
Hollyhock is BoJack's half-sister whom he originally believed to be his daughter when she first showed up. While the pair's relationship as siblings was strong at first, it became strained the more she learned about him and came to an end in the final season.
Hollyhock is played by Aparna Nancherla, a comedian that has been a writer on Totally Biased with W. Kamau Bell in addition to Late Night with Seth Meyers. She has also provided the voice of Kishy on Ginger Snaps, appeared on Inside Amy Schumer, and portrays Grace Ramaswamy on Corporate.
J. K. Simmons As Lenny Turteltaub
Lenny Turtletaub is a Hollywood producer that is responsible for helping create a lot of films in the industry including BoJack's film debut, Secretariat, and the action film Ms. Taken.
Lenny is played by J.K. Simmons who has had countless roles in film and TV. His work includes voicing Tenzin on The Legend of Korra, playing Vernon Schillinger on Oz, and starring as Howard Silk on Counterpart. His movie roles include Bob from Up in the Air and his Oscar-winning performance as Terence Fletcher in Whiplash.
Wendie Malick As Beatrice
Beatrice Horseman is BoJack's abusive mother whom he blames for a lot fo the emotional issues he has as an adult due to her treatment of him when he was a child.
Beatrice is played by actress, Wendie Malick who played Nina Van Horn in Just Shoot Me!, Judith Tupper Stone in Dream On, and as Victoria Chase in Hot in Cleveland. She is also known for playing Ronee Lawrenceon on Frasier. Malick also had many character roles in movies, including Scrooged, The American President, and Confessions of a Shopaholic.
Kristen Schaal As Sarah Lynn
Sarah Lynn is a former child actor turned signer that starred in Horsin' Around with BoJack as Sabrina. As she got older she became addicted to drugs and alcohol which led her to revisit her connection with BoJack before her early death at the age of 31.
Sarah Lynn is played by Kristen Schaal who is most recognized for her voice roles as Mabel on Gravity Falls and Louise on Bob's Burgers. She is also known for playing Hurshe Heartshe from The Heart, She Holler, Mel from Flight of the Conchords, as well as Carol Pilbasian from The Last Man on Earth. Other characters of hers are Amanda from The Hotwives of Orlando, Anne on Wilfred, and Hazel Wassername from 30 Rock.