Rex Coughlin

In Hana Lokomaika'i, he and another agent question the Five-0 team about Chin Ho's involvement in his father's case as well as arresting Gabriel Waincroft, not caring about the facts given to him. When Chin Ho walks out, he taunts him by saying he'll be waiting.

In Pono Kaulike, Coughlin arrests Chin for his role in Marco Reyes' murder, also still believing Chin did it for money and Gabriel was willing to testify. But as Coughlin gave him a pen to sign the statement, Gabriel uses the opportunity to stab him in the eye before taking off with his gun and phone. Without him, all charges against Chin Ho were dropped and Waincroft sarcastically called him using Coughlin's phone saying he is welcome.