As previously announced, Robert Wagner will guest star on the 150th episode of NCIS in the critical role of Tony's dad.

But he isn't the only big name coming to TV's top-rated show for that special edition. Penny Johnson Jerald will reprise her role as State Department Official Joanne Torrence on the January 12 installment of the drama, titled "Flesh and Bone."

The actress is best known for her role as Sherry Palmer on multiple seasons of 24.

During this landmark episode, the NCIS team investigates attempted assassination of a foreign prince. Without giving too much away, we can confirm that Tony's father is linked to the case.

Says Rocky Carroll (Director Vance): “You find out that there’s a strained relationship between the two.”

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.