UPDATE, WEDNESDAY AM: The behind-the-scene drama on Sam & Cat is not subsiding. I hear the show has been put on a “permanent hiatus” a few episodes early, samcatwith everyone on the crew let go except for those working in post-production.

PREVIOUS, TUESDAY PM: Nickelodeon‘s comedy Sam & Cat has been a runaway success by any measure. The series, from proven hitmaker Dan Schneider, brought together two popular characters from two popular Nick series — iCarly’s Sam Puckett and Victorious‘ Cat Valentine — played by two of the network’s best-known stars and best friends, Jennette McCurdy and Ariana Grande, respectively. The series has been a ratings hit, quickly becoming Nickelodeon’s highest-rated series. In July, only a month into Sam & Cat’s run, Nick doubled its freshman order from 20 to 40 episodes. Its hourlong January 18 episode drew 4.8 million total viewers and ranked as Nick’s highest-rated telecast with kids 6-11 in two years.

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But as Sam & Cat is wrapping production on its 40-episode first season, there is no word on Season 2 — a very unusual development for such a successful series. There has been talk about discord on the set, with emotions running high and McCurdy and Grande sometimes showing up late. The grueling, 40-episode shoot has been taxing on everyone. Additionally, McCurdy had been going through a difficult time in her personal life for the past six months and recently had to deal with the leak of racy photos, while Grande’s music career has taken off a big time. Both have been at Nickelodeon for a long time, McCurdy for more than seven years and Grande for more than four. Both are entering adulthood, and word is both feel constrained at kids-focused Nickelodeon and are ready to move on.

I hear things came to a head last week when the show came close to a shutdown. Then this past weekend, McCurdy publicly accused grancekcaNickelodeon of unfair treatment. She also fueled speculation about a rift with longtime best friend Grande by un-following Grande on social media and not joining her co-star at Nickelodeon’s Kids Choice Awards, where both were nominated for favorite TV actress. (Sources close to the situation note that McCurdy and Grande are still getting along fine.) Sam & Cat was a big winner, taking Favorite TV Show, Favorite TV actress (Grande) and Schneider receiving a Lifetime Achievement Award. McCurdy took to Twitter to explain her absence from the awards show, which she had been scheduled to attend. “I was put in an uncomfortable, compromising, unfair situation (many of you have guessed what it is) and I had to look out for me,” she wrote. “I chose to not go because sticking up for what is right and what is fair is what my mom taught me is ALWAYS the most important thing. I want to thank those of you who have reached out with kind words of support, McCurdians and Arianators alike. No matter who or what you support, I believe in supporting fairness first.” She later clarified her decision to boycott the awards had nothing to do with the release of the photos. “It has to do with how Nickelodeon treated me,” she said. “That’s all.”

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The behind-the-scenes issues have complicated Nickelodeon’s decision how to proceed with the series. I hear there is a Season 2 production start date penciled in for later this year, but a renewal decision still appears to be a toss-up. “We are wrapping up what was an unusually long production cycle of Sam & Cat, and everyone is understandably tired,” the network said in a statement. “We are going into our production hiatus next week which will give everyone on the show a much needed rest.” While Nick brass still hope for another season of Sam & Cat, they also have lined up potential reinforcements, greenlighting three new live-action comedies earlier this month, including the 20-episode Henry Danger from Schneider.