Castle star Nathan Fillion has officially signed on for future seasons of the crime procedural, but the show is now without a showrunner.

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News came out Thursday morning that Fillion (Castle) had finally signed the deal to continue starring in the show. ABC had been through renegotiations with Fillion and his co-star Stana Katic (Beckett) due to both of their contracts running up at the end of season 7.

Fillion renewing his contract makes a possible season 8 pretty likely, though it will be without showrunner David Amann. The boss stepped into the role at the beginning of season 7 after original series creator Andrew W. Marlowe stepped down. It is not known why Amann will no longer be showrunner.

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Ultimately, losing Katic might be more significant for the show overall. If she does not sign the contract to continue with the series, then that would create an awkward new dynamic that ABC may not want to have with the series. Therefore, if Katic does not sign on for more Castle then the network could potentially decide to cancel it.

It is also possible that ABC could cancel the show even with Fillion and Katic on board for more. Seven seasons is a long time for any show and they may decide that this is the best move creatively for the series.

Castle currently airs every Monday at 10 p.m. ET/PT on ABC.

Watch the promo for the next episode of Castle here:

Tags: Castle television ABC