Summary

• Leslie Mann and Paul Rudd return as the focus of This Is 40 shifts onto their marital struggles.
• A new version of Jason Segel's character returns in This Is 40.
• Alison and Ben are the two biggest characters from Knocked Up that don't appear in the sequel.

This Is 40 sees the return of characters from the 2007 comedy, Knocked Up. Both films are directed and written by Judd Apatow and feature comparable storylines. Knocked Up was largely focused on Alison (Katherine Heigl) and Ben (Seth Rogen) as they navigate life as soon-to-be parents, despite their ill-timed circumstances. Knocked Up also stars Leslie Mann as Alison's sister, Debbie, and Paul Rudd as her husband, Pete. The latter couple have relationship issues of their own, but spend most of their time helping out Alison and Ben. This Is 40 changes this and catches up with Debbie and Pete five years later.

Both films share similar themes that showcase the unpredictability of romantic relationships and family life. Many of the main characters from Knocked Up return in This Is 40, such as the children of Debbie and Pete, but other characters, most notably Ben and Alison, are absent from the sequel. Judd Apatow has addressed this inconsistency in This Is 40, saying he didn't feel the need to introduce an older Ben and Alison because, in many ways, that's what the marriage between Debbie and Pete represents.

7 Jodi

Played by Charlyne Yi

Knocked Up features a group of individuals living together while working to set up their website. Among the group is Charlyne Yi’s Jodi, who is first introduced when Alison comes by the house for the first time. Jodi is under the influence at this time and, as a result, she's known for her odd commentary. Yi's minimal appearance is the extent of her part in Knocked Up, yet she returned to portray Jodi once more in This Is 40. Five years after the events of Knocked Up, Debbie owns a boutique and Jodi is an employee.

None of Jodi's dialogue mentions her roommates from Knocked Up, but in a humorous confrontation between Jodi and Debbie, audiences learn the character still uses drugs. Debbie discovers Jodi stole money from the company and while firing her, she mentions a previous time when Jodi babysat Debbie's children while under the influence of drugs. Jodi appears to be unbothered by her actions and, due to her odd behavior, it's assumed she's high during their conversation. This is the last time Yi is on-screen and while her part in This Is 40 is still minor, Jodi's character played a large part in Debbie's troubles.

6 Dr. Pellagrino

Played by Tim Bagle

As Dr. Pellagrino, Tim Bagley returns to This Is 40 and delivers the same news to Debbie as he previously shared with her sister Alison. In Knocked Up, Dr. Pellagrino confirms to an unsure Alison that she is indeed pregnant. Upon receiving the news, Alison breaks down into tears, overwhelmed with panic. Similarly, Dr. Pellagrino tells Debbie she is pregnant. Just like her sister, Debbie did not plan her pregnancy and her reaction is reminiscent of Alison's.

Bagley's role is minor, and ultimately Debbie's pregnancy does not take up as much of the plot as Alison's. Debbie is struck with panic and stress due to her financial and marital complications with Pete, but spends the majority of This Is 40 keeping the news to herself. Pete only finds out in the film's third act and audiences don't see what happens to the couple once the baby is born. Dr. Pellagrino's dialogue had a greater impact on Alison's life than it did Debbie's, but his return in This Is 40 adds to the film's overall continuity from Knocked Up and it's comical for audiences to see the sister's nearly identical reactions.

5 Jason

Played by Jason Segel

Ben's group of friends in Knocked Up consists of characters played by Martin Starr, Jonah Hill, Jason Segel, and Jay Baruchel. Each actor has appeared in other Apatow productions, but only Segel returned in This Is 40 as his character Jason. The version of Jason in Knocked Up spent most of his days at home and smoking marijuana. Additionally, Jason helps out with the group of guys and takes the time to log the timestamps of particular movie scenes, as they're setting up an adult website. This Is 40 shows a version of Jason that's almost unrecognizable.

Jason now works as Debbie's trainer (or as he views himself, her "spiritual guide"). During a workout session early on in This Is 40, Jason encourages Debbie's pursuit of fitness and lends a friendly ear as she vents to him about her marital strains. Keeping in line with his actions from the first film, Jason tends to subtly flirt with Debbie. However, the two don't discuss the previous years of their connection or their relationship with Ben and Alison. Jason doesn't appear in any other setting in the film, other than when he attends Pete's 40th birthday party and competes with another man for a woman's attention.

4 Sadie

Played by Maude Apatow

Judd Apatow's daughters star in his projects quite often, and they both return as their characters, Sadie and Charlotte, in This Is 40. Throughout much of her dialogue, Sadie (Maude Apatow) has a distinct sense of humor. One of Knocked Up's most memorable scenes is when Sadie explains her understanding of having a baby to the adults at the table. Sadie's explanation is the best representation of Apatow's young talent, as it's equally hilarious and adorable. Sadie and her sister Charlotte don't take up much time in Knocked Out, but their scenes perfectly set up the growth of their characters in the sequel.

Sadie is 13 years old by the time This Is 40 takes place and her teenage view of the world adds additional stress to an already tense period for Debbie and Pete. Debbie decides to change the family's lifestyle, which includes minimized screen time, but Sadie struggles the most with this change. She enjoys spending her time binge-watching the entirety of Lost and chatting with her friends on social media. The latter gets herself and her parents in trouble with another teenager at school and results in one of the film's more memorable scenes when Debbie and Pete confront the teenager's mom, Catherine, humorously played by Melissa McCarthy.

3 Charlotte

Played by Iris Apatow

The daughters of Debbie and Pete are much younger in Knocked Up, with their youngest, Charlotte (Iris Apatow), being a toddler. Most of Apatow's scenes were with other actors, including a scene in which Sadie and Charlotte are playing outside with Ben and he begins to play fetch with the latter. Charlotte did not speak as much as her older sister, but still provided sweet and endearing reactions to the surrounding characters. In This Is 40, Charlotte is now eight years old and both her presence on-screen and her comedic timing improve, allowing her personality to shine through.

Amid all the teenage angst Sadie lets out on their parents, Charlotte is watching from the sidelines delivering commentary and attempting to lighten up the mood. Similarly to the first film, Charlotte's reactions to others are charming as she wants nothing more than to spend time with her sister. Charlotte asks if she can watch Sadie's current TV obsession with her, Lost, and retrieves her sister's technology for her after their parents have taken it away. The sisterly dynamic is much stronger in the sequel and seamlessly ties into the film's overarching portrayal of a realistic family unit.

2 Debbie

Played by Leslie Mann

Helping Alison through her unplanned pregnancy in Knocked Up, Debbie's relationship is a minor part of the film's overall story. She momentarily suspects Pete is cheating on her, and though he wasn't, Debbie finds herself hurt by the fact that he feels as though he needs to lie about his whereabouts. The contention between Debbie and Pete acts as a reminder for Alison of what she doesn't want her relationship with Ben to turn out like. Additionally, Debbie has brief moments in Knocked Up where she is insecure about her age, which is most apparent when she's at the club with her sister.

The relationship Debbie has with her age continues in This Is 40 and though her denial about turning 40 is presented comically, it’s a widely understood feeling by audiences and adds another realistic element to the film. The marital conflict from the first movie returns in the sequel and Debbie is at odds with Pete about money and communicating with one another. Fortunately, the two understand the importance of overcoming these disputes and manage to do so. Furthermore, Debbie patches things up with her distant father and it's assumed the two's relationship remains strong past This Is 40's ending.

1 Pete

Played by Paul Rudd

In Knocked Up, Pete finds himself detached from his marriage with Debbie and often lies to her about his feelings. Pete expresses being overwhelmed by the family and needing time for himself, but this upsets Debbie and the two spend time apart. It isn't until Pete is under the influence of psychedelic mushrooms that he comes to his senses and wishes to make amends with Debbie. Otherwise, Pete largely acts as a supporting character, helping out with his children and accompanying Ben on a trip to Las Vegas. Five years later in the sequel, he's running his own record label.

Juxtaposing Debbie's emotions, Pete is content with turning 40, though many of his immature emotional responses to the conflict in his marriage remain, including lying and acting distant. Debbie is missing money from her boutique and the outdated artists at Pete's record label aren't making enough money for the company. The couple's money-related issues continue when Pete lends money to his father and lies to Debbie about doing so. The couple's relationship is realistic and a reflection of what many audiences have experienced. Altogether, This Is 40 builds on the tasteful balance of comedy and drama that begins in Knocked Up.