A new sneak peek for the midseason premiere of ABC's Castle features Rick (Nathan Fillion) making his big debut as a private investigator.

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With Castle no longer working for the 12th Precinct, he has decided to go about solving crimes another way, through private investigating. The rascally novelist turned detective gets his P.I. license online and decides to conduct a parallel investigation against the 12th.

In a sneak peek for Castle, P.I., the next episode of Castle, the character is shown making his grand entrance on the crime scene, much to the chagrin and confusion of Beckett (Stana Katic).

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"I'll take it from here," he proclaims as Beckett and the gang investigate a murder.

When Beckett protests and says that he is not allowed to be there, Castle clarifies, highly amused with himself.

"Actually I am. Because I'm not longer Richard Castle, ordinary citizen, I am now Richard Castle, Private Investigator."

He then tells her that he simply took an online course, but Beckett doesn't think it will repair things with the district attorney.

"The P.I. license doesn't change anything. The D.A.'s still not gonna let you investigate with us," she observes.

He then announces that he will be conducting a "parallel investigation alongside yours" and the two continue back and forth comically.

It remains to be seen how long Castle will continue to be private investigator but hopefully it will be entertaining enough and provide a nice dynamic change for a little while.

Castle returns Monday at 10 p.m. ET/PT on ABC.

Watch the sneak peek for the next episode of Castle below:

Tags: Castle television ABC