EXCLUSIVE: I learned this morning that Tom Selleck hasn’t been accepting the scripts which CBS’ Blue Bloods executive producer Ken Sanzel has been giving him. So a standoff developed over character vs procedural visions for the series, summarized to me as “creative tension”. By midday, Sanzel was still staying with the show. No more. Insiders just emailed me that the former New York cop told the staff late today that he is leaving. There’s no exit date yet. “He’s a stand-up guy; he won’t leave the network or studio hanging,” a network source explains. “Simply creative differences. It happens. He was brought in after the pilot as a showrunner to set the show up. We often do this for pilots picked up to series that have great writers but who haven’t run shows before.” Now, to replace Sanzel, Selleck wants to find ”his guy” who must also meet with studio/network approval. Unfortunately this turmoil is especially embarrassing because it’s executive produced by Leonard Goldberg, a CBS Corporation board member.

Sanzel, a longtime Numb3rs showrunner, was handpicked by CBS and CBS Studios to executive produce with creators Mitchell Burgess and Robin Green, who continue with the show. ”Ken is a real take-charge tough guy and everyone knows it. They begged  him to take the show. He was reluctant to do it. And Selleck was not crazy to have Ken imposed on hm. But Ken was doing the network bidding thanklessly,” an insider tells me. Sanzel’s vision was for a compelling crime procedural, whereas Selleck wanted softer character exploration. Sanzel knew the network was behind him. But Selleck wanted to be in charge of the show.  “Too many cooks,” one of my insiders explains. “They love him at CBS. But Selleck realized it’s not the show he thought he was in. Ken calls Nina Tassler and says, ‘What do you want to do?’ And she says, ‘Let me talk to Tom.’” Today, it became clear to me it was just a matter of hours before Sanzel left the show. ”Not bail on them in one day. Just saunter off peacefully,” a source tells me. “If we were to count up every single show where there’s creative friction between actors and producers, we’d have a number like the census bureau.”

At first considered a long shot (“pilot #10 of 10″), Blue Bloods made it onto the schedule seemingly because of Selleck’s stardom and Goldberg’s juice. It even inherited Numb3rs’ Friday 10 PM time slot this fall. And Sanzel himself was a New York cop before becoming a writer. CBS traditionally teams the limited experience creators of its newly picked-up series with seasoned showrunners after the pilot. Sanzel ran Numb3rs for most of the crime procedural’s 6-season run on CBS and has an overall deal at CBS Studios. This development season, he wrote, directed and executive produced the CW pilot presentation Nomads.

Blue Bloods is the first hour-long drama Selleck has headlined since Magnum, P.I. from 1980 to 1988. And he’s back with CBS where had a half shortlived half-hour sitcom The Closer and in more recent years the Jesse Stone telepics made from Robert B. Parker’s mystery novels. Originally titled Reagan’s Law, the new series is a drama about 3 generations of a storied police family. Selleck plays a widower and the current NYPD chief.

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