Jonah Hill first entered the Apatow Universe with a cameo in The 40-Year-Old Virgin before becoming a star in his own right, appearing in Apatow's Knocked Up, Walk Hard: The Dewey Cox Story and Forgetting Sarah Marshall before headlining Superbad with Michael Cera. Hill also had a role in the Apatow-directed Funny People and went head-to-head with Russell Brand in Get Him to the Greek. Outside of the Apatow Universe, he was nominated for both a Golden Globe and an Oscar for his supporting role in 2011’s Moneyball.
The sun in the Apatow Universe, Seth Rogen appeared as the wise-cracking Ken Miller in Freaks and Geeks and worked as a writer on Apatow's other short-lived television show, Undeclared. Rogen went on to appear in Apatow-affiliated films including Anchorman (as a cameraman), The 40-Year Old Virgin (as the tattooed stock-dude Cal) and as Ben Stone in Knocked Up. The collaboration continued with Superbad and Pineapple Express (Rogen co-wrote both films), as well as a cameo in the Apatow-produced Step Brothers. Rogen also starred in Funny People, which Apatow directed.
After starring in Freaks and Geeks as the ultimate bad boy, Daniel Desario, James Franco has linked up with Apatow twice more: he made a cameo as himself in Knocked Up and starred alongside Rogen as a pot dealer in Pineapple Express. Since getting his big break, he has starred as Harry Osborn in the original Spider-Man trilogy, delivered a noteworthy performance in Milk and was nominated for numerous awards – including a Golden Globe and an Oscar – for his starring role in 127 Hours. He also made an uncredited cameo in Rogen’s 2011 reboot of The Green Hornet.
How I Met Your Mother star Jason Segel appeared in both Apatow's Freaks and Geeks and Undeclared. After a breakout role as Seth Rogen's housemate in Knocked Up, Segel took the lead in the Apatow-produced Forgetting Sarah Marshall, which he also wrote. He then co-wrote and co-produced Get Him to the Greek and The Five-Year Engagement. This Is 40 represents the fourth time Segel and Paul Rudd have worked together.
Since appearing as recovering nerd Lindsay Weir in Freaks and Geeks, Linda Cardellini hasn't linked back up with Apatow. But she starred as Velma in the Scooby-Doo series, played Cassie Cartwright in Brokeback Mountain and starred on ER. Cardellini also played a bit part behind the scenes of Forgetting Sarah Marshall – the infamous nude breakup was based on an actual relationship-ending talk with real-life boyfriend Jason Segel.
John Francis Daley, who played Lindsay's pesky younger brother Sam Weir on Freaks and Geeks, went on to appear in numerous television shows and the film Waiting alongside Ryan Reynolds and Justin Long. He currently appears on Bones as Dr. Lance Sweets.
Another veteran of both Freaks and Geeks and Undeclared, Samm Levine also appeared in Quentin Tarantino's World War II epic Inglourious Basterds and starred in Not Another Teen Movie, Sydney White and Club Dread. He’s currently the sidekick on the Internet talk show Kevin Pollak’s Chat Show.
Actress Busy Phillips followed up her role as bitchy Kim Kelly on Freaks and Geeks with recurring parts on Dawson's Creek and ER. The godmother of Matilda Rose Ledger, the daughter of Heath Ledger and Michelle Williams (Phillips' Dawson castmate), Phillips has since gone on to appear in Made of Honor and He's Just Not That Into You. She currently stars in the Courtney Cox comedy Cougar Town.
Jay Baruchel was neither a freak nor a geek, making his Apatow debut as the star of Undeclared before moving on to Knocked Up as one of Rogen's roommates. Baruchel also had a major role in Ben Stiller's Tropic Thunder, portrayed a young Led Zeppelin fan in Almost Famous and overdosed as a freshman in The Rules of Attraction. He voiced the starring role in the animated feature How to Train Your Dragon and its many franchises.
McLovin! Christopher Mintz-Plasse nearly stole Superbad, followed it up with a spot in Paul Rudd's Role Models and starred in the Apatow-produced Year One. Since then, he’s appeared in Kick-Ass, the Fright Night remake and voiced a character in How to Train Your Dragon alongside fellow Apatow alum Jay Baruchel.
One of the most versatile and prolific of all the Apatow players, Paul Rudd has earned top marks for comedic roles in The 40-Year-Old Virgin, Knocked Up, Anchorman and many more. He's appeared in nearly every Apatow film since Anchorman, starring alongside Jason Segel in I Love You, Man and popping up in the Apatow-produced Year One. This Is 40 marks his ninth collaboration with Apatow.
Apatow and Leslie Mann first met while working together on the 1996 film The Cable Guy. They married in 1997, and Mann has appeared in every movie he’s directed since, plus Drillbit Taylor and Freaks and Geeks. Their daughters, Iris and Maude, have appeared in Knocked Up, Funny People and This Is 40 as the offspring of Mann's respective characters.
Saturday Night Live alum Kristen Wiig made a splash in the Apatow Universe as a passive-aggressive TV producer in Knocked Up, then went on to appear in Walk Hard: The Dewey Cox Story and Forgetting Sarah Marshall. But the pair hit paydirt when they worked together on the box office smash Bridesmaids, which Apatow produced. The screenplay was nominated for an Oscar.
Although a star on Mike & Molly at the time, Melissa McCarthy became a household name after practically stealing the spotlight from Kristen Wiig in the Apatow-produced Bridesmaids. She even nabbed a Best Supporting Actress nod at the Oscars. With a role in This Is 40, she may just become one of the major players in the Apatow Universe.
Apatow and Will Ferrell first teamed up on Anchorman: The Legend of Ron Burgundy and the straight-to-DVD Wake Up, Ron Burgundy: The Lost Movie. (So far the only two movies Apatow himself has appeared in.) Ferrell then starred in Kicking & Screaming, Talladega Nights: The Ballad of Ricky Bobby and Step Brothers. They have partnered together on comedy video website Funny or Die and the related HBO series Funny or Die Presents, and they are re-teaming for an Anchorman sequel.
Steve Carell first stepped into Apatow’s world as dim meteorologist Brick Tamland in Anchorman: The Legend of Ron Burgundy, but he really blew up when he starred in The 40-Year-Old Virgin – which in turn helped boost the ratings for his TV show at the time, The Office. Carell made a cameo in Knocked Up, and he will reprise his breakout Anchorman role in the sequel.
The controversial hit HBO series Girls, starring Lena Dunham, is executive produced by Apatow, who has also written for the show. It’s been nominated for numerous awards, winning a Primetime Emmy. Dunham’s first foray into an Apatow film comes with This Is 40, in which she plays one of Paul Rudd’s character’s employees.