NBC's Up All Night looks like it may finally be put to sleep.

Sources tell The Hollywood Reporter that the network is strongly considering abandoning the plan to keep the struggling series alive in the wake of star Christina Applegate's exit last week. As a planned one-episode reboot of the show has stalled, co-star Will Arnett is being seriously courted by CBS to star in a Greg Garcia-written comedy, among others.

In addition, sources tell THR that co-star Maya Rudolph has informed NBC that she is pregnant with her fourth child with director Paul Thomas Anderson. These sources say the show's writers planned to incorporate the pregnancy into the revised version of the series, but that issue could now be moot. The show's writing staff is said to be seeking new jobs.

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NBC and reps for the actors declined to comment.

Initially, the network hoped to salvage the Lorne Michaels-produced comedy, hiring veteran James Burrows to tape one episode of a largely re-imagined show with Arnett and Rudolph. (It was not clear whether the Applegate role would be recast after her abrupt decision to quit.) But that reboot has hit snags and Arnett is said to be ready to move on.

NBC has not released Arnett or Rudolph from their contracts for the original Up All Night, a single-camera show that the network hoped to transform into a multi-camera, behind-the-scenes look at a struggling television series. The show is not officially dead, though presumably the stars' exits are being negotiated.

The chaos comes at a key time for Arnett and Rudolph, with casting on the nearly 100 broadcast pilots already under way and both actors rocketing to the top of many network wish lists. Both Arnett and Rudolph have already received second-position offers for a number of broadcast pilots. CBS' Les Moonves in particular is said to want Arnett for an untitled comedy written and executive produced by Garcia about a recently divorced man whose parents move in with him. ABC also is high on the actor.

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In the past two months, Up All Night has seen creator Emily Spivey and showrunner Tucker Cawley exit, with new showrunner Linda Wallem (Nurse Jackie) charged with retooling the series.

NBC announced in December that Up All Night would resume production in February following a three-month hiatus, with five episodes scheduled to begin in April or May. That plan was later changed to a one-episode reboot. The creative changes would have marked the latest for the comedy this season after Rudolph's talk-show format was ditched in the season two premiere earlier this fall.

Lesley Goldberg contributed to this report.