Dr. Malia Waincroft was the wife of Detective Lieutenant Chin Ho Kelly (2010) and who was also a pediatric oncologist employed at Honolulu Hospital.
It was originally assumed that Malia had dumped Chin but in actuality, Chin was the one who had broken it off during his investigation by Internal Affairs.
Malia wore her engagement ring on a chain around her neck during Season 1. In Season 2, Chin and Malia reconnected and during the episode, Kil'ilua (episode), Chin proposed to Malia a second time and she accepted. Later, while the team were fleeing North Korea after rescuing Steve from Wo Fat (2010), Chin told them that he was getting married and he asked Lieutenant Commander Steve McGarrett (2010) to be his best man.
The couple were eventually married in Alaheo Pau'ole (episode) with Officer Kono Kalakaua (2010) as one of Malia's bridesmaids while Detective Sergeant Danny Williams (2010) and Kamekona Tupuola were Chin's groomsmen and for a year and a half, Chin and Malia lived a happy life together up until the Season 2 finale episode, Ua Hala (episode) where Chin was blackmailed into breaking Frank Delano with Delano revealing that Malia and Kono had also been take hostage while he forced Chin to choose between the two.
Chin chose Malia and later contacted Adam Noshimuri to inform him that Kono was in danger. By the time he got home, Chin found Malia on the floor, bleeding heavily from a gunshot wound.
In the Season 3 premiere episode, La O Na Makuahine (episode), paramedics tried to save Malia but the injuries were so severe that she eventually succumbed to her wounds and died, leaving Chin grief-stricken and completely devastated.
In the aftermath of Malia's death, Chin, numb also became obsessed with getting revenge against Delano and later succeeded in doing so by shooting Delano dead in cold blood in a underground parking lot.
In Kanalua (episode), the team attended Malia's funeral.
In Hana Lokomaika'i (episode), we learn Malia had a brother Gabriel, who had been arrested 15 years before.