Netflix’s Big Mouth is jam-packed with celebrity cameos, new voices, and returning guests that ensure season 5 is the wildest to date. Big Mouth is loosely based on Nick Kroll and Andrew Goldberg’s formative years in suburban New York, where the two boys navigate the hellish landscape of puberty with the help of their assigned hormone monsters. Netflix’s Big Mouth has developed a massive following across its five seasons to date, with a raft of celebrity character and cameo Big Mouth voices now attached to the project, which first won plaudits for its advertised shameless approach “towards embracing a frankness about the human body and sex.”
Big Mouth season 4 ends with a titanic struggle for Nick’s soul after his body is taken over by his darker future self, “Nick Starr.” Kaiju-style battles ensue, with Zack Galifinakis’ Gratitoad clashing with the giant Anxiety Mosquito inhabiting Nick’s psyche before Nick’s normal persona is finally restored. Big Mouth season 5 has clearly taken cues from the prior season’s zany finale. Its fifth season immediately introduces talking penises, fresh hormone monsters, and new sexual entities known as the Love Bugs.
Big Mouth season 5 has certainly upped the proverbial ante, with huge stars such as Hugh Jackman and Kumail Nanjiani joining an already sweeping voice roster for the Netflix original. Familiar favorites such as Jordan Peele’s Ghost of Duke Ellington and Maria Bamford’s Tito and Nancy also return in relatively minor capacities for the latest Big Mouth installments, although these two regulars are not considered guests in this context. Here’s every celebrity guest and who they play in Big Mouth season 5.
Kumail Nanjiani as Himself
Kumail Nanjiani is a prominent advocate for “No Nut November” in Big Mouth season 5, with the actor’s fictional cartoon persona stating that abstinence has single-handedly changed his life. While a relatively minor role in comparison to the actor’s recent turn in Eternals as Kingo, Nanjiani does get to voice some apparent grievances with Amazon’s handling of his movie The Big Sick. Nanjiani also stars in HBO’s Silicon Valley as Dinesh Chugtai, the Java programmer.
Hugh Jackman as Himself (Sort-Of)
The most bizarre and high-profile cameo in Big Mouth season 5 is courtesy of Hugh Jackman, who plays a bizarre bit-part role. In “No Nut November,” Maury gives a shout-out to a penis that looks like Hugh Jackman in one of his seminars, with Jackman himself voicing the phallic character. Jackman is pure A-list by any set of criteria, with the Australian-born actor best known for his iconic portrayal as X-Men‘s Wolverine as well as his numerous stints on Broadway.
Adam Scott as Mr. Keating
Parks and Recreation legend Adam Scott lends his voice to the character of Mr. Keating in Big Mouth season 5, the new English teacher at Bridgeton Middle School. Keating’s “cool teacher demeanor,” complete with swearing and jumping on students’ desks, leads to Andrew becoming entranced by his teacher after Keating makes Shakespeare seem cool. In addition to his aforementioned role as Ben Wyatt, Scott has also starred in comedies such as The Good Place, Stepbrothers, and Party Down.
Jemaine Clement as Simon Sex
Flight of the Concords‘ Jemaine Clement appears throughout Big Mouth season 5 as Simon Sex, a less aggressive hormone monster who is Maury’s best friend. Simon helps Andrew tap into his sensitive side by teaching him to relax around the opposite sex while also providing hilarious back and forth with his other hormone monster counterparts. Clement’s other comedy outings include turns in the vampire-centric What We Do in the Shadows, Dinner for Schmucks, and Wellington Paranormal.
Chloe Fineman as Leah Birch
Chloe Fineman has taken over the role of the rebellious Leah Birch from her previous voice actor, Kat Dennings, although the reasons for this recasting remain unclear to date. Leah continues to push her parent’s boundaries in Big Mouth season 5 while also teaching her little brother Nick how to be “cool.” Fineman has been a Saturday Night Live regular since 2019.
Pamela Adlon as Sonya the Lovebug
The Lovebugs introduced in Big Mouth season 5 are a new form of an imaginary creature designed to help the Bridgeton Middle students understand the romantic feelings they are beginning to have for one another. Sonya is Jesse’s assigned Lovebug who helps her navigate her changing attitudes towards several of her classmates, including her long-time friend Nick Birch. Adlon is best known for voicing Bobby Hill in the cult-classic animation King of the Hill.
Brandon Kyle Goodman as Walter the Lovebug
Walter is the other prominent Love Bug featured in Big Mouth season 5; only he is instead assigned to Nick, whose confidence he helps build back up after his disastrous “Nick Starr” episodes in season 4. Walter also aids Nick in his long-standing pursuit of Jesse’s affections as the pair attempt to move Nick out of the dreaded “Friendzone.” Goodman has previously appeared in season 11 of Curb Your Enthusiasm and will reprise his role as Walter in the upcoming Big Mouth spin-off series, Human Resources alongside Shrill star Aidy Bryant.
Keke Palmer as Rochelle the Hate Worm
If the Lovebugs are the fuzziest form of an adolescent companion to date in Big Mouth, then Keke Palmer’s Hate Worm is one of the most loathsome. Rochelle the Hate Worm monster ingrains herself in Missy’s brain, helping her hatred fester for her classmates and family that have long frustrated her in Big Mouth. Keke Palmer is a Nickelodeon alum who has since enjoyed a successful musical career with her first studio album released in 2007.
Fred Armisen as Elliot Birch
The Portlandia co-creator returns once again for Big Mouth season 5 to voice the head of the Birch household Elliot. As free with his body as he is open about love and interpersonal relationships, Elliot has long since been a source of embarrassment for the Birch children, with Nick, in particular, struggling to be around his effervescent father. Armisen has enjoyed a long and successful comedic career, with his nine-year SNL stint backed up by cameos in classic comedies such as Eurotrip, Deuce Bigalow: European Gigolo, and Anchorman: The Legend of Ron Burgundy.
David Thewlis as The Shame Wizard
The Shame Wizard is the mortal enemy of the Hormone Monster who inflames kids’ deepest shame, forcing them to retreat into their proverbial emotional shells. The primary antagonist of season 2, the Shame Wizard, has become a fan-favorite recurring character in Big Mouth whose dry and scathing examinations of the Bridgerton Middle School students’ lives are a great source of humor for the Netflix series. The Shame Wizard is voiced by David Thewlis, who is best known for his role as the werewolf-teacher Professor Lupin in the Harry Potter film series.
Nathan Fillion as Himself
Returning cameo character Nathan Fillion continues to play a fictionalized version of himself in Big Mouth season 5. Fillion exists primarily in the Netflix series as a figment of Missy’s imagination, as she uses a daydream-version of her celebrity crush to help her on her journey through puberty. Nathan Fillion has an avid following for his other television projects, the most prominent of which are the infamously canceled Firefly and ABC’s Castle.
Richard Kind as Marty Glouberman
Marty Glouberman, Andrew’s grumpy, overbearing, and stereotypically Jewish father, dips in and out of the Big Mouth narrative but is back with a vengeance in season 5’s events. In addition to eating an unhealthy amount of scallops, Marty often gives unwise advice to his adolescent son, which inevitably causes young Andrew more social and emotional trouble. Marty is voiced by Richard Kind, who is best known for his voice work in various Pixar movies such as A Bug’s Life, Cars, and the Toy Story film series.
Zachary Quinto as Aiden
Best known for his fan-favorite roles as serial-killer Sylar in Heroes and a young Spock in J. J. Abram’s Star Trek movies, Zachary Quinto returns to Big Mouth season 5 as the continued voice of Aiden. Aiden is Matthew’s (now) long-term boyfriend, with the two actively protesting the undercurrent of homophobia that runs through Big Mouth‘s fictional suburban New York setting.
Zach Galifinakis as the Gratitoad
After his climactic showdown with the Anxiety Mosquito, Zach Galifinakis’ Gratitoad is back for Big Mouth season 5 and ready to teach the children of Bridgeton Middle School all about being thankful. Galifinakis rose to fame following his outrageous performances as Alan Garner in The Hangover movie trilogy, with his Big Mouth character Gratitoad adding a similarly zany feel to the series’ proceedings. The American-born Greek actor has more recently won acclaim for his celebrity interview series Between Two Ferns, which more often than not descends into bizarre non-sequiturs, awkward product endorsements, and inappropriate guest questions.
Chelsea Peretti as Monica Foreman-Greenwald
More colloquially referenced across Big Mouth‘s seasons as “Missy’s Mom,” Monica comes to the fore in Big Mouth season 5 as she battles Rochelle the Hate Worm’s continued grip on her daughter. Monica is voiced by Brooklyn-Nine-Nine star Chelsea Peretti, who also boasts impressive writing credits that includes Pawnee’s Parks and Recreation and several Saturday Night Live segments.
Kristen Schaal as Bernie Sanders
Andrew Glouberman’s winter vacation is forever changed when he meets Bernadette Sanders, a girl who finds his every action enthralling. Bernie’s inside joke that she shares a name with a certain prominent Vermont senator is only the tip of the iceberg for voice actor Kristen Schaal’s comedic talents, who has risen to prominence as the voice of Louise Belcher in the beloved animated series Bob’s Burgers. Schaal has recently starred as The Guide in the hit comedy series What We Do In The Shadows and voices various characters in the long-running Netflix animation Bojack Horseman.
Mark Duplass as Val Bilzerian
One half of Jay’s tormentors-in-chief, Val Bilzerian, typifies an older brother from hell as he continues to wreak unmitigated destruction in Big Mouth season 5’s story. Mark Duplass voices this aggressive Bilzerian brother, with the American actor and filmmaker best known for creating his own horror franchise Creep.
Paul Scheer as Kurt Bilzerian
Kurt is Jay’s other older brother who, together with Val, conspire to make Jay’s home-life a living hell. The equally combustible recurring Bilzerian brother is voiced by comedian Paul Scheer in Big Mouth season 5, whose impressive acting credits also include stints in Veep and Fresh Off the Boat.
