Meka Hanamoa is a Detective and Detective Danny Williams' former partner at HPD who was murdered while investigating corruption within the department.
He was married to a woman named Amy and had a young son named Billy. When Danny arrived on the island and was transferred to the HPD, he and Danny became partners. Meka and Danny became close friends as Danny also became well acquainted with Meka's family. In regards to their detective work, Meka enjoyed working with Danny as he had a different and fresh perspective and their friendship and partnership grew to the point where Meka completely trusted Danny with his life. Overall, Meka thought of Danny as the best partner he ever had.
Meka is revealed to have been murdered, being discovered shot twice, with his body burned beyond recognition and his police badge stuffed in his mouth. Danny is deeply saddened to learn of his death, meeting a distraught Amy who reveals the news. Danny is determined to find Meka's killer and prove Meka's innocence, learning Internal Affairs believed that Meka was guilty of corruption. Throughout the investigation, Danny never believed Meka was corrupt and continued to protect and defend his name when it appeared that Steve began to suspect Meka might be corrupt. Eventually, thanks to Hawaii Five-0, Meka was eventually cleared of all charges, as he was investigating corruption within the HPD and was killed upon discovering the identity of the mole, Detective Kaleo.
In the flashback episode, Wehe 'ana, taking place before Danny was assigned to work the murder case of Steve's father, John McGarrett, eventually leading him to join the Hawaii Five-0 Task Force, Meka and Danny work together to solve a murder case and display a good friendship and partnership as Meka stands by Danny when their Police Captain Chan Tanaka is giving Danny a hard time. Meka sees that Tanaka is being unfair towards Danny when a potential witness goes missing, and Tanaka holds Danny responsible. When Tanaka pulls Danny off the murder case to investigate the death of John McGarrett, Meka assures Danny he isn't at fault for what happened to the missing witness.