When Dexter is looking at Philip Bosso's Personnel Record on his computer, it can be seen that the Performance Evaluations were written by a ''Cpt. Mark Harmon''. [ Mark Harmon is the name of the actor playing one of the lead roles on ''NCIS''.]
The trivia items below may give away important plot points.
This episode highly references the show Supernatural. A guest star is the actor Jim Beaver, who played the main role in supernatural named Bobby. This is the name that the arsonist is writing on all of his crime scenes. The name of the phantom arsonist is Joseph Jensen, a reference to one of the other main actors of supernatural, Jensen Ackles.