The Season Finale of Hawaii Five-0 airs on Friday amidst a frenzy of cast changes, one of them being the addition of two recurring characters to regular roles.

A Cop’s Cop

Back in November came word that Chi McBride (Captain Lou Grover) would become a regular cast member of the Five-O reboot. McBride had premiered his character in the series and walked the red carpet at the Sunset on the Beach Premiere Event for Season Four. At the time of his arrival on the carpet, he had just come from the set where he had spent the day filming the Jerry Levine-directed Episode 8, “Akanahe” (Reluctant Partners). At that time, he confided to me that he had been riding a horse all afternoon and had no idea what he was doing. He joked that he had no problem as long as the horse thought he knew what he was doing. At the time of his promotion to “regular” status, Executive Producer Peter Lenkov, in a statement, revealed the ease in which McBride slid into the Grover role and his easy fit into the Five-0 ohana (family).

Conspiracy Anyone?

As the season progressed, in Episode 3, “Ka’oia i’o Ma Loko” (The Truth Within), Lost alum Jorge Garcia debuted the ever-so-suspicious conspiracy theorist Jerry Ortego to help the Five-0 team solve a case involving the Royal League and the Kamehameha Statue. By the time March rolled around, it was announced that he too had been promoted to series regular. At the time of the announcement, Lenkov said, “Jorge very quickly made Jerry an unlikely and valuable part of the Five-0 ohana. We have many opportunities planned to put Jerry’s unusual and infectious desire to get the bad guys to good use.”

Fan Play

Fans got a rare opportunity to build an episode of the series in October. Over a period of several weeks, they voted through cbs.com on the elements of crime scene, victim, murder weapon, evidence, suspect, and takedown. After much anticipation, Episode 18, “Ho’i Hou” (Reunited) was broadcast in April.

Exit Catherine Rollins

As Season Four was on winding down, surprise word arrived that Michelle Borth (Catherine Rollins) would not return to the series in the fall. Episode 21, “Makani ‘olu a holo malie” (Fair Winds and Following Seas), where her character enlists the help of McGarrett (Alex O’Loughlin) to help her retrieve the son of a friend from the hands of the Taliban, aired last week and marked her final appearance on the series.

Where Do We Go from Here?

With this whirlwind of activity, viewers enter the airing of the Finale on Friday, May 9 with unanswered questions regarding Wo Fat’s mother’s now-empty grave in Cambodia and the continuing mystery of why McGarrett’s mother allowed Wo Fat to escape in the Season Four Premiere. McGarrett discovered early on in the season that he and Wo Fat are not half-brothers, but why the secret regarding Wo Fat’s mother? Did Doris have an affair with Wo Fat’s father? Did she raise Wo Fat after all? Is Doris even McGarrett’s real mother?

What lies ahead for Season Five can only be speculation at this point. The cast is on hiatus until mid-July, when a Hawaiian blessing will again open the new season for filming. Word is Episode Three will be the first shot, with Joe Dante directing and Carol Burnett reprising her role as Mary (Taryn Manning) and McGarrett’s Aunt Deb. Burnett debuted this character in Episode 9, “Hau‘oli La Ho’omaika’i” (Happy Thanksgiving) of Season Four.

Hawaii Five-0 airs its season Finale on Friday, May 9 with “O ka Pili’Ohana ka ‘Oi” (Family Comes First) on CBS at 9 P.M.