There are almost countless reasons why Sex Education has been such a hit for Netflix. The series tackles important subjects, has great LGBTQ+ representation, and is both poignant and hilarious, all making it succeed. Another major factor is just how talented the cast is.

RELATED: 10 Times Sex Education Tackled Deep Issues

That goes for the young actors who are just starting their promising careers and for the veterans who bring the show's adults to life. They've all appeared in a handful of notable roles outside of the series. Of note, one main cast member not included is Aimee Lou Wood, who has no other feature film or TV parts to date but did win a BAFTA and has some key stage roles.

Jemima Kirke - Girls (Stream On HBO Max)

Jessa at a desk in Girls

Season 3 saw the addition of Hope Haddon (Jemima Kirke) to the cast as the new headteacher at Moordale Secondary School. She quickly became the main antagonist of the series, using her outdated and often unhealthy views of the world to embarrass and upset her students.

In 2012, Jemima Kirke had her breakout role, starring as Jessa Johansson in more than 50 episodes of HBO's Girls. The show followed a group of female friends living in New York City, with Jessa typically coming across as the coolest one of the bunch.

Simone Ashley - Bridgerton (Stream On Netflix)

Simone Ashley as Olivia in Sex Education

One thing that Sex Education has done well with is expand on characters who started out as just background players. For example, the popular trio known as The Untouchables have all found deeper storylines as things progressed. One member is Olivia, played by Simone Ashley.

Another of the show's youngest talents, Ashley has a blossoming career right now. She had small appearances in films like 2019's Detective Pikachu but just added another huge Netflix series to her resume. In the upcoming season 2 of Bridgerton, she'll be playing Kate Sharma.

Mimi Keene - EastEnders (Not Available To Stream Or Rent)

Ruby at the bowling alley with Eric and Adam in Sex Education

Ever since season 3 was released, fans everywhere can't seem to stop talking about the show-stealing performance of Mimi Keene as Ruby Matthews. Of all of The Untouchables, she got the most development as Ruby's relationship with Otis led to her home life being explored.

Although Keene is still young, she has actually been on television for a long time. She appeared in over 100 episodes of the British soap opera EastEnders as Cindy Williams. There are also smaller parts in films like Tolkien and Close for Keene, with big ones likely on the way.

Alistair Petrie - Rogue One: A Star Wars Story (Stream On Disney+)

Alistair Petrie in Rogue One

The first true veteran performer included is Alistair Petrie. The actor has been working steadily since the 2000s and it's clear that one of his biggest roles is as Mr. Groff, the former headteacher at Moordale. He's a villain at first who finds some redemption in season 3.

RELATED: The 15 Best Characters In Sex Education, Ranked

Considering the lengthy career of Petrie, it should come as no shock that he shows up in all sorts of roles, including 2019's Hellboy. However, most fans likely will recognize him as General Draven in 2016's Rogue One: A Star Wars Story.

Kedar Williams-Stirling - Small Axe (Stream On Prime)

Kedar Williams-Stirling in Lovers Rock

The seemingly impeccably handsome Jackson Marchetti is played by Kedar Williams-Stirling. He's one of the most interesting characters as he evolves a lot throughout the series, deals with panic attacks, forms heterosexual friendships, and might enter into a queer romance next season.

Like so many of his castmates, Williams-Stirling is someone who is only starting to get the biggest roles of his career. He has appeared on shows like Wolfblood and movies like Changeland. A part worth checking out is his turn as Clifton in "Lovers Rock" of Small Axe.

Connor Swindells - Emma. (Stream On HBO Max)

Robert Martin in Emma

Along with Ruby, the show-stealer in season 3 of Sex Education was Adam Groff, played by Connor Swindells. Audiences loved watching him branch out and become more comfortable in his sexuality, as well as his heartfelt attempts to simply be a better person.

His career is also just launching but he managed to land the role of Robert Martin in the 2020 Jane Austin adaptation of Emma. Interestingly enough, the film also featured Tanya Reynolds, who plays Lily Iglehart on Sex Education.

Ncuti Gatwa - The Last Letter From Your Lover (Stream On Netflix)

Eric looking upset in Sex Education

For a lot of fans, Eric Effiong is their favorite character. He's brought to life by Ncuti Gatwa, who infuses Eric with his electric charisma. Eric is one of the series' many LGBTQ+ characters and his journey of self-exploration and acceptance is a highlight.

RELATED: 9 Friendships Nobody Saw Coming On Sex Education

Again, Gatwa is an actor who is just starting to break out, with his role as Eric being the most prominent and earning him two BAFTA nominations. Outside of the character, Gatwa popped up in 2021's The Last Letter From Your Lover as Nick, alongside Felicity Jones and Shailene Woodley.

Emma Mackey - Eiffel (Rent On Vudu)

Emma Mackey dances in Eiffel

Get ready to hear Emma Mackey's name a lot more in the coming years. The talented actress became an instant sensation as Maeve Wiley, one of television's best female characters. She's bright, powerful, likable, and basically a modern TV icon.

Mackey recently landed the biggest role of her career away from Sex Education as she will portray Jacqueline de Bellefort in 2022's Death on the Nile. She also just recently played Adrienne Bourgès in Eiffel, which is her biggest film role to date. She feels like a true rising star in Hollywood.

Gillian Anderson - The Crown (Stream On Netflix)

Gillian Anderson as Margaret Thatcher sitting and arguing in The Crown.

No actor on this series is more seasoned or established as Gillian Anderson. She arguably steals every scene she's in as Jean Milburn, the mother of the protagonist and a sex therapist. She is at the heart of some of the most important scenes regarding sexuality.

There are plenty of roles from Anderson's career that stand out as being great but two top them all. First, there was her longstanding run as Dana Scully on The X-Files but more recently, she earned an Emmy Award for her turn as Margaret Thatcher on The Crown.

Asa Butterfield - Then Came You (Stream On Netflix)

Asa Butterfield watches Maisie Williams spray paint in Then Came You

The entire show may feature a great ensemble of characters and actors but at the center of it all is certainly Otis Milburn. Played by Asa Butterfield, Otis is a socially awkward teen who begins giving out sex advice alongside Maeve, thanks to his knowledge of his mother's work.

Although he's still young, Butterfield has been all over the place in movies. There was 2008's The Boy with the Striped Pajamas, 2013's Ender's Game, and 2017's The Space Between Us. A good place to see him play something somewhat close to Otis is 2018's Then Came You, where he portrays Calvin Lewis, a teen who befriends a girl dying from cancer.

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