"Hawaii Five-0" bridged the past and present to remember the deadly attack on Pearl Harbor on Dec. 7, 1941. The episode "Honor Thy Father" started with a flashback to "the day which will live in infamy."

After the flashback, the characters are shown at a Pearl Harbor Day commemorative ceremony at the real site of the attacks. McGarrett (Alex O'Loughlin) spots an elderly Japanese man trying to kill one of the veterans at the ceremony. McGarrett is able to apprehend the man, and takes him to 5-0 for questioning.

The man's name is David Toriyama (James Saito), and he is seeking revenge on Ezra Clark, the veteran, because he claims the man killed his father in 1943.

There is another flashback that shows David as a young boy with his older brother, Kenji (Conrad Pratt), who were living with their parents in Hawaii at the time of the Pearl Harbor attacks.

The scenes show how Japanese residents were taken from their homes and put into internment camps. During his backstory, David says it felt like they were POWs. He says his father was murdered, but it was covered up because he was Japanese.

McGarrett and Catherine (Michelle Borth) go to meet Ezra, who at first seems like he's an old racist, but it turns out he has a Japanese wife and daughter.

The team then goes to David's home to continue the investigation, where McGarrett recognizes his grandfather in an old photo, who was in the Navy and died during the Pearl Harbor attack.

Danny (Scott Caan), McGarrett and Chin (Daniel Dae Kim) go to an old storage facility, where they find files from 1943. They find a witness report that says Ezra Clark is the witness, not the offender. 

The go back to the site of the internment camp to jog David's memory about the murder, but he still insists that Ezra Clark was the killer. Evidence from the paperwork then shows that the cop who may have covered it up is named George Rigby.

The team goes to the Rigby home, and eventually find out that they need to find the bullet that killed David's father to crack the case.

They exhume the body and find the bullet. After some tests, they find out that the murderer was not Ezra Clark. It turns out the murderer was Joseph Archer, the little brother of a guard at the camp, who shot him with a .38 gun. David then apologizes to Ezra for his misconception. 

At the end of the episode, McGarrett is back with David at the USS Arizona memorial. David tells him that he knew his grandfather, and that they even played catch together. And with that, David hands McGarrett his baseball mitt.

On the next episode, "Pukana" (Keepsake), "Chin's life is placed in danger when a murder investigation reveals that the culprit may be a serial killer. Meanwhile, Danny and Grace find a mysterious puzzle box that washed up on shore in Oahu."

Watch the promo for "Pukana" below, which airs Friday, Dec. 20 at 9 p.m. on CBS.