Last week on "Hawaii Five-0," Danny (Scott Caan) chaperoned Grace's (Teilor Grubbs) winter formal, but things took a frightening turn when terrorists seized the venue and held everyone hostage in order to kidnap a diplomat's son. Later, Grace's boyfriend introduced himself to Danny, and the boy turned out to be Lou's (Chi McBride) son, Will Grover (Chosen Jacobs).

Danny's ex was unavailable to chaperone Grace's dance, so she asked him to fill in for her. Danny took this as a good opportunity to spy on his daughter, as he suspected that she may have started dating someone.

At the dance, Danny started following Grace around, telling her that he would stop once he met her boyfriend. Later, Will approached Danny and introduced himself as Grace's boyfriend, and immediately, Danny called his Five-0 teammate to tell him that their children are now dating each other.

The two ended up arguing on the phone, but things started to get scary on the dance floor as some gunmen started looking for Jeremy Ramos (Max Tepper), the son of a Philippine diplomat. The men wanted him in exchange for their leader who was imprisoned in the Philippines. With Will's help, the Five-0 was able to save everyone at the dance, and Danny and Lou took their children to a burger place where they could have their first dance.

This week, in the episode titled "Elua la me Nowemapa" which translates to "Two Days in November," the Five-0 investigates one of history's most notorious unsolved mysteries when a conspiracy theorist is murdered. It turns out that the victim has uncovered compelling evidence which shows that John F. Kennedy's cabinet ordered his assassination in November 1963.

In the promo for the episode, Jerry (Jorge Garcia) is talking to a young woman when she gets shot by an unseen assailant. Jerry tells Steve (Alex O'Loughlin) that the woman was "about to tell the world and they killed her," and Steve asks, "You're talking about the Kennedy assassination?"

"She solved it," says Jerry.

Later, Danny talks to Steve and says, "We're not going to stand down, are we?"

"Nope," Steve replies.

"Hawaii Five-0" airs Fridays at 9 p.m. EST on CBS.