Castle Season 5: Behind the Scenes With Seamus Dever and Kevin Daniels (PHOTOS)

Modern Family actor Kevin Daniels is the latest Hollywood star to stop by the set of Castle for a Season 5 guest spot. Although we don't know much about his role on the hit crime procedural, we do know he's been having a grand ol’ time filming it.

"Having a blast on the #Castle set with @seamusdever," he tweeted on August 9, along with the above picture.

On August 10, Seamus returned the Twitter love, posting this photo of Kevin "in the box."

We're loving this on-set bromance between the pair, but something tells us their on-screen relationship won't be so smooth. If Kevin's character is chilling in the interrogation room, we can only assume he's a suspect. And we all remember what happened in "Kick in the Ballistics," right? Detective Ryan, FTW!

Are you looking forward to Kevin's guest spot? Tell us below!