Andrew Marlowe, the showrunner of "Castle" since the first season, is set to handover primary duties and responsibilities to David Amann, the executive producer of the show.

Marlowe, however, is expected to continue having a day-to-day presence on the show. According to reports, he has stepped-down to concentrate on developing new projects as part of his overall deal with ABC Studios.

Marlowe's successor Amann joined the "Castle" team during the third season in 2010. He has written some of the most talked about episodes of the show, including "After the Storm," "Under Fire," "Disciple," "In the Belly of the Beast," and "That 70s Show."

"David has proven himself to be a tremendous leader and a great steward of our show's unique voice. I'm excited to continue our creative collaboration as he assumes his new responsibilities," Marlowe said in a statement.

"Castle" will return this fall for Season 7, with a new mythology. The new season will pick-up right where it left-off. The Season 6 of the show wrapped-up with Beckett finding Castle's car in a ditch and in flames and Castle nowhere in sight. Castle and Beckett were all set to get married.

In one of his interviews, Marlowe had said that they wanted to introduce a new mythology with a "bang" and thus ended Season 6 with a big question mark on Castle's fate. He also said that Castle and Beckett will have their kind of wedding but there is still some storytelling to do before these two get married.

Nathan Fillion has signed on for Season 7, Marlowe had confirmed. He also had dropped a hint that Castle is alive by saying that he plays the "titular" character.

It is unlikely that there will be much change in the script of the new mythology, or the love-story arc of Rick Castle and Kate Beckett. As Marlowe continues to be associated with "Castle," the fans may continue to see his little imprints on the show.