Christina Applegate kisses 'Up All Night' goodbye

Christina Applegate is going to bed.

The former Married... With Children co-star is leaving NBC's Up All Night due to creative differences. The sophomore comedy has experienced its share of upheaval and had been in the process of shifting from a single-camera format to a traditional multi-camera setup, although the planned five new episodes have yet to be filmed.

"It's been a great experience working on Up All Night, but the show has taken a different creative direction and I decided it was best for me to move on to other endeavors," explained Applegate. "Working with Lorne Michaels has been a dream come true and I am grateful he brought me into his TV family. I will miss the cast, producers and crew, and wish them the best always."

Produced by Saturday Night Live overlord Lorne Michaels, Up All Night was originally developed as a family comedy about new parents Reagan and Chris Brinkley (Applegate and Will Arnett), inspired by series creator Emily Spivey's experiences returning to work soon after giving birth. Applegate had recently had a baby and identified with the concept, but when Maya Rudolph was cast as her boss, the workplace element was expanded and changed from a public relations firm to a TV talk show starring Rudolph's character.

The show is no stranger to turnover behind the scenes, including the departures of Spivey, original showrunner Jon Pollack, and his replacement Tucker Cawley. Due to mediocre ratings for the first 11 episodes of the second season, NBC announced that Up All Night would be revamped as a multi-camera comedy and begin filming in front of a live studio audience.

With Applegate scheduled to start shooting the Anchorman sequel this month, NBC may be planning to move ahead with Up All Night despite the loss of its lead star. Some sources indicate the network is looking at Friends star Lisa Kudrow as a potential replacement, although her producing partner Dan Bucatinsky has denied the possibility on Twitter.

Whatever they decide, it's going to be tricky. It would be too dark to have Applegate's character killed off or abandon her husband and baby. Unless the plan is to cut Arnett out too and have the show focus solely on Rudolph's character with Kudrow (or someone else) as her new producer after Reagan and Chris suddenly and unexpectedly move away.

What do you think? Should NBC just put Up All Night to sleep and develop new projects for Will Arnett and Maya Rudolph, or could the show have new life with a retooled concept?