Hawaii Five-0: Season 4

Before McGarrett can get answers about his mother from Wo Fat, terrorists break into the prison and also take hostages at Five-0 headquarters.

A hard-as-nails Texas Ranger arrives on the island to look for his missing daughter, Kono and Adam's secure location is compromised, and an old friend comes to Catherine with a job offer.

A married couple's execution leads Five-0 to a mystery involving stolen artifacts and a long-forgotten secret society, and Catherine goes through her last day with the Navy.

As Five-0 deals with the murder of an ex-con wedding crasher, McGarrett and Danny are forced to deal with problems in their relationships.

McGarrett tries to find the man who killed his old SEAL friend Billy while he and Catherine were working a surveillance job, and he also turns to Joe White to track down his mother.

After a "zombie attack" at a Halloween party, Five-0 discovers a mad doctor who is conducting bizarre human experiments.

Five-0 tries to figure out who killed an officer who was working undercover for the ATF, while also babysitting for McGarrett's sister Mary's new baby.

McGarrett and Grover reluctantly work together to issue a summons to a young man who turns out to be a dangerous cyberterrorist.

A Secret-Servince agent's death leads Five-0 to believe that an assassin is targeting the President during his trip to Hawaii; McGarrett gets a surprise Thanksgiving visit from his Aunt Deb.

A murder attempt on a Pearl Harbor veteran leads Five-0 to use decades old evidence to investigate a deadly crime committed in an internment camp on Oahu during WWII.

While investigating a homicide during an attempted home burglary, Five-0 stumbles onto a serial killer, and Chin Ho may be his next victim.

When Captain Grover's friend disappears, Five-0 discovers that his friend was hiding a dangerous secret. Meanwhile, Danny befriends a New Yorker new to the island, and Kono reunites with Adam.

Internal Affairs questions Chin about his father's murder 15 years ago and his relationship with Malia.

A convicted murderer escapes from custody, holds McGarrett and Danny hostage, and claims that he was framed for the crime.

Five-0 investigates the murder of a real estate agent, Danny's mother comes to Hawaii with big surprise news, and captain Grover reveals a secret about his past to McGarrett.

Five-0 investigates a triple homicide connected to a downed top-secret Chinese satellite, while Grover takes Danny's mother on a ride-along.

Five-0 looks for a 16-year-old girl who is kidnapped after her father is murdered, Danny launches a plan to keep his mother from getting a divorce, and Jerry uncovers a new clue for McGarrett related to "Shelbourne."

One of Chin Ho and Jerry's high school classmates is killed during their class reunion, and McGarrett and Danny find a new clue at the secret burial site.

McGarrett and Danny are trapped in the rubble of a blown-up building after an informant's tip on a gun buy goes wrong.

The team uncovers an Islamic terrorist plot involving American college students.

While Five-0 investigates a homicide related to a stolen transplant organ, McGarrett joins Catherine for a trip to Afghanistan so she can help a friend whose son has been kidnapped by the Taliban.

Cyber-criminal Ian Wright holds Grover's daughter hostage and demands that Grover help him out with a multi-million dollar heist. Meanwhile, Wo Fat escapes from maximum security in Colorado.