The exec is close to accepting an offer from Warner Bros. to get into the feature business. The well-liked Cherniss, who joined Fox in May 2008, will likely remain at the network through the end of the upfront season, when his contract expires.
But the exec is free to start entertaining opportunities now, and Warner Bros. is said to be high on giving him the opportunity to try the movie waters. Cherniss was said to also be in high demand from other quarters, including cable nets.
Reilly and former Fox chairman Peter Liguori recruited Cherniss in the job to replace former Fox No. 2 Craig Erwich, who's now also over at Warner Bros. — but still in television, as the head of Warner Horizon.
According to insiders at the network, Cherniss' position will not likely be filled, at least for now. Instead, it's more likely that drama chiefs Terence Carter and Lindsay Sloane, as well as comedy toppers Suzanna Makkos and Marcus Wiley, will now be handed more oversight.
Reilly previously operated without a top lieutenant in the months following Erwich's exit and prior to Cherniss' arrival.
At Fox, Cherniss had a hand in the development of hits such as "Glee" and this year's "Raising Hope."
Before that, Cherniss was senior VP of original programming, FX drama and comedy series development. He had moved to FX as director of drama and comedy development in 2002.
At FX, Cherniss played a major role in the development of recent drama skeins "Damages," "The Riches" and "Dirt." He also had a hand in the development of "Nip/Tuck," "Rescue Me," "It's Always Sunny in Philadelphia" and "30 Days."
This was the second tour of duty at Fox for Cherniss, who first joined the net in 1994 in the research department; he moved over to programming in 1998, handling shows such as "Melrose Place" and "Malcolm in the Middle."