Christina Applegate, Maya Rudolph, Will Arnett

The first season of Up All Night ended on a high note, with Chris (Will Arnett) finally getting to propose to Reagan (Christina Applegate) the way he'd always dreamed. But don't expect everything to be romance and rainbows when the show returns for its sophomore season Thursday at 8:30/7:30c. Creator and executive producer Emily Spivey and producer Tucker Cawley spoke to TVGuide.com about the huge changes coming to this season, which kicks off with some very bad news for Reagan and Ava (Maya Rudolph).

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No More Ava Show, No More Diva

The first season of the NBC series was a balancing act between Reagan's home and her workplace, but in Season 2 the creators decided to shift the focus away from the office, cutting out The Ava Show completely. "We canceled The Ava Show just because we wanted Ava to be a little more aspirational and not the diva, floating above everyone," Spivey explains. Without the show as a crutch, Ava sets off to find herself this year — a journey that includes yoga, celebrity endorsements and dabbling in the home-shopping world.

But while Ava looks optimistically toward her future, she must also come to terms with her past. "She's sort of having to, at the moment, make amends for being this larger-than-life, inconsiderate, diva person that she was when she had the show," Spivey says. One of the people she has to make amends with: Sean Hayes, who plays Walter, Ava's former accompanist-turned-nemesis, after she ditched him for stardom. But while Ava works to restart her friendship with Walter, don't expect the pair to restart Ava's music career -- though Cawley says their reconciliation will be musical in nature.

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Cast Shakeups

With the cancellation of The Ava Show, we not only lose a lot of great parodies of daytime TV, we lose Ava's better half: Missy (Jennifer Hall)! Cawley regretted to inform us that — at least for now — the world's most spastic personal assistant has ordered her final honeydew swan. (Hopefully Hall took the cancellation news better than Missy did when she thought she got fired.)

This season we'll meet Reagan's newly divorced brother Scott (Luka Jones), whose laid-back attitude could not be further from his sister's controlling personality. "They kind of help each other," Spivey explains. "When she's getting too uptight, he brings her out of it and when he's kind of lost, she helps him get it together." Still, they have one fundamental disagreement: parenting. (Scott has a 7-year-old son).

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Trading Places

Reagan is now unemployed, but being a full-time mom isn't exactly as she imagined. "Reagan's now at home and having to deal with being a Type-A kind of producer trying to micromanage everything domestically, which turns out to be a lot harder than she thought it would be," Spivey says.

With Reagan at home, Chris takes the opportunity to head back into the workforce, but the 18 months he spent with Amy shifted his priorities a bit. Instead of returning to the law firm, Chris decides to start up a small construction business with Scott. "He wanted to be able to point to a building or a restaurant and say to his daughter, 'Look, I built that,' as opposed to just racking up billable hours," explains Spivey.

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Do We Hear Wedding Bells?

We've seen the Bonnie Tyler-scored engagement, but now it's time for the wedding! Spivey revealed that this season will feature a flashback episode to Chris and Reagan's nuptials. "They were definitely career people who worked hard and played hard," Spivey explains of the couple's extended adolescence before Amy. In addition to an expected array of questionable '90s hairstyles, the episode will also feature Blythe Danner, who will return as Reagan's mom.

In case you're wondering, as of now, Chris and Reagan are the only couple who will walk down the aisle this season. Due to scheduling conflicts, Kevin (Jason Lee), who proposed to Ava in the Season 1 finale, is not yet scheduled to appear this year. But that doesn't mean Ava will be a spinster by any means! In fact, early this season we'll see Ava fall for Chris' college roommate Jerry (Rob Huebel). Too bad Chris and Reagan absolutely can't stand him. Awkward!

What do you think of all the changes for Season 2? Up All Night premieres Thursday, Sept. 20 at 8:30/7:30c.