: After retiring from the Navy to join Five-0, her tenure is cut short by a "debt of honor" that takes her to Afghanistan, marking her departure from the main cast.
Critics and fans alike viewed Season 4 as a period of maturation. While some noted that the show occasionally "jumped the shark" with outlandish scenarios—such as the rescue mission in Afghanistan—the central "cargument" banter between McGarrett and Danno remained the series' emotional anchor. According to reviewers from TV Fanatic , the season successfully balanced serialized drama with procedural "case of the week" episodes, culminating in a high-stakes finale involving the kidnapping of Grover's daughter. Hawaii Five-0 - Season 4
The most significant addition this season is (played by Chi McBride), the former Chicago PD SWAT commander whose initial friction with Steve McGarrett (Alex O'Loughlin) eventually evolves into mutual respect and full team membership. This dynamic provides a fresh perspective on the team's "immunity and means" status, as seen on Fandom . : After retiring from the Navy to join