ABC boss explains why 'Castle' and 'Nashville' were canceled

'Nashville' Cast 'Blindsided' By Cancellation
'Nashville' Cast 'Blindsided' By Cancellation

Why did ABC opt to cancel bubble dramas Castle and Nashville?

After publicly firing Castle's Stana Katic and signing new contracts for five other stars, including lead Nathan Fillion, the show's dismissal was seen as the season's most perplexing move. With Nashville, producers Lionsgate Television had already signed respected writers Marshall Herskovitz and Ed Zwick (My So-Called Life, thirtysomething) as new showrunners for season five. So what was behind those two major decisions?

"At the end of the day, we didn't feel that even though Castle and Nashville were wonderful shows and good performers for a long time, the future for us didn't lie in those shows," new ABC Entertainment Group president Channing Dungey told reporters during an early conference call ahead of her presentation to Madison Avenue ad buyers Tuesday. She stressed that ABC Studios (Castle) and Lionsgate TV (Nashville) were looking for the best creative and financial ways for both series to work, while the network was examining what was the best fit for everything on its schedule. "Looking at ratings, our own finances and looking at new development, decisions came down to the wire, which is the difficult thing about these jobs as we weigh and measure different things."

See photos from ABC's "Nashville" below:

Sources tell THR that Castle season eight showrunners Alexi Hawley and Terence Paul Winter filmed two versions of what wound up being the May 16 series finale -; one for if the ABC Studios-produced drama was renewed in which Katic's Beckett would have likely been killed off, and the other in which the fan-favorite couple lived happily ever after. Many industry observers had noted talks were under way for a 13-episode final season after cutting costs (the likely reason behind Katic's dismissal).

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In its eighth season, Castle had been a sturdy performer for ABC on Mondays. With seven days of DVR, the drama has averaged a 2.0 rating among adults 18-49 and 10 million total viewers. Monday's series ender scored a season high. A final season would have allowed the network as well as returning showrunners Winter and Hawley -; who boarded in season eight -; to properly close out what had been a profitable series for the studio. For their part, the showrunners said in a statement Monday night that they were "still trying to process all the emotions stirred up by recent events" and called Beckett and Rick Castle a "love story for the ages." (Unlike The Good Wife creators, Winter and Hawley canceled a round of press calls for Tuesday following news of Castle's cancellation.)

Read MoreInside Stana Katic's Shocking 'Castle' Exit

Sources told THR in April, following Katic's dismissal -- which caught most of the cast and crew by surprise -- that ABC considered writing out Beckett at the end of season seven but balked when the network faced backlash after Patrick Dempsey's Derek Shepherd was shockingly killed off and written out of Grey's Anatomy with a year remaining on his contract. Insiders note that Katic and Fillion did not get along and clashed repeatedly with the duo having limited scenes together.

Read MoreCritic's Notebook: 'Castle' Series Finale Strikes a Sour Note

For Nashville's part, the drama was one of the few not included in ABC's 15-show renewal spree in March, and also one of the network's only dramas from an outside studio. However, the decision to cancel the Connie Britton and Hayden Panettiere starrer was still surprising. The series enjoyed a sizable DVR boost, up to a 1.9 rating among adults 18-49, and enjoyed ancillary profits from soundtracks and concert tours.

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ABC instead will launch Hayley Atwell drama Conviction in Castle's home on Mondays at 10 p.m., while Kiefer Sutherland's Designated Survivor will take over Nashville's slot on Wednesdays at 10 p.m.