The FBI's assistant director of national security joins the BAU as it investigates the quadruple homicide of a group of roommates in St. Louis.
The BAU is called when the New Orleans Police Department discovers a mass grave inside a vandalized above-ground crypt in a local cemetery.
When Mac is put into a dream state to help him recall key evidence found in Nikola Tesla's secret lab that could stop Codex's deadly plot, he encounters Nikola Tesla, Alexander Graham Bell, Thomas Edison and his mother.
Los Angeles' power grid is taken hostage in a ransomware attack resulting in a citywide blackout the team discovers the ransomware code used was written by Riley years ago.
After Oversight is almost killed in a bombing, he recruits Mac to help him find the suspected bomber Mac meets his Aunt Gwendolyn.
A double date descends into chaos when Mac and Desi witness a murder in the back of the restaurant as they work to find the killer, Riley tries to keep the secret about her and her friends' "day jobs' from her new boyfriend.
When Russ' first love, Emilia, is kidnapped by the same rebels he fought during his private military contract days, he takes the Phoenix team to a small, impoverished town to rescue her and rid the town of the rebels for good.
Two young people filming a documentary about a Hawaiian burial site are murdered during the investigation, a drifter (Robert Englund) puts a curse on Danny.
McGarrett takes part in a charity MMA fight while investigating a wealthy restaurateur's murder NCIS Agent Kensi Blye examines a video of McGarrett's father.
The Five-0 is targeted by Wo Fat after getting too close to the truth about the criminal mastermind and his associates.
After receiving valuable information from Agent Jenna Kaye, the team closes in on Wo Fat Danny is exposed to a deadly neurological agent.
After a famous photographer is murdered while doing a magazine shoot, Danny is happy to learn that he will be interviewing the swimsuit models.
While on a hike, Danny and McGarrett find a murder victim Chin Ho and Kono go home to visit their ailing aunt.
A science-fiction fan dressed as a superhero is murdered McGarrett receives a visit from a CIA agent interested in finding Yakuza.
The team must stop a vengeful bomber Danny's fun-loving brother (Dane Cook) visits unexpectedly.
An afternoon pleasure cruise turns into a nightmare when pirates attack and take hostages.
Horatio must fire a member of his team when the problems of that person taint the current investigation.
A nasty divorce gets worse when the husband's mistress turns up dead, and the body count continues to rise as the complicated relationship unravels.
On Christmas Eve, a boy is trapped in a beach-side cave, where the rising tide threatens his life the team races to find a way to save him.
Sylvester ends up in critical condition after accidentally triggering an explosion during an investigation the team must remain focused on finding the culprit.