Chin Ho is kidnapped from his home in the middle of the night, drugged, and then dropped right in the heart of Halawa prison, dressed as an inmate. With the help of Sang Min, who Chin Ho helped put in prison, he tries to keep his head down so that none of the inmates recognize him as Five-0. Chin's Five-0 family slowly discovers the kidnapping and races to break him out of prison before he's killed by vengeful inmates. A prison riot ensues, with former cop Kaleo leading the charge, and he eventually corners and beats Chin Ho. Five-0 arrives in the nick of time, subdues the rioting inmates, and saves Chin's life. During the chaos, Sang Min manages to escape, though Chin Ho isn't keen to go after him because he owes the fugitive his life.
Meanwhile, after witnessing Adam take a very distressing private phone call, Kono's suspicions about his private dealings increase. She has Fong trace the number that the call came from, but that leads to a dead end. Left with few options and fearful for Adam's safety, she decides to secretly clone his phone at the end of the episode.