Watch Castle Season 4 Online
In Castle season 4, Castle and Beckett come face to face with zombies, show dogs, Elvis and a live tiger. Watch Castle Season 4 online so you don't miss a minute of the fun, the drama or the romance.

Beckett is hot on the trail of the person who shot her mother. Read on for a recap of the Castle season finale.

A zombie attack on Castle?!? That's the theory that starts to fly on this season four episode.

It's a Firefly reunion on Castle this week, as Adam Baldwin guest stars in the fun role of Detective Ethan Slaughter.

Brett Tucker guest stars this week as a detective from Scotland Yard. He teams up with Beckett and Castle on a personal case.

A bomb goes off during a protest this week, causing Castle and Beckett to go back over the timeline of the event, and also to evaluate their lives.

Castle delves into the world of reality TV this week, as a contestant on "A Night of Dance" is murdered n her dressing room.

The detectives look into the deaths of women dressed as fairytale characters while Martha puts on a one woman show.

This is the conclusion of the annual two-parter. It features Castle and Beckett racing to stop a chain of dangerous events from unfolding.

Castle and Beckett are after a killer this week, which leads them to a major conspiracy. Jennifer Beals guest stars.

Told through flashbacks, Castle and the detectives investigate a murder linked to a double homicide in the 1940's.

The murder of a dog trainer/judge has Castle and Beckett looking into guest star Hilarie Burton's character, Kay Cappuccio, a character resembling reality star Kim Kardashian.

The detectives investigate a murder which leads back to Castle's friend, Mayor Welden.

Ryan prepares to get married and the detectives look to solve the murder of a pick up artist.

Castle and Beckett wake up handcuffed together with no memory of the situation. Time to find out what happened!

A sniper is making waves in NYC, causing Beckett to deal with her PTSD. Castle and Esposito do their best to help her through the situation.

An Atlantic City casino owner is found dead in NYC leading to a bachelor party for Ryan on the latest episode of Castle.

A bank robbery goes bad when Castle and Martha are held hostage inside. Find out what happened in the latest episode of Castle now!

Castle and Beckett hunt down the murder of a famous ghost hunter on the latest installment of Castle.

Kristin Lehman guest stars this week as Serena Kaya, an insurance investigator who helps out Beckett & Castle when a murder and robbery takes place at an art museum.

Uh-oh. The gun used in a murder this week is discovered to be Det. Ryan's former service weapon. That can't be good.

A missing body leads the detectives into the world of cryonics and Alexis gets news from Stanford.

Beckett & Castle track down a vigilante named Lone Vengeance through the city and make some headway with Captain Gates.

On the fourth season premiere of Castle, Beckett's fate is found out and the detectives meet their new captain. Will Castle & Beckett reconnect? Find out in our review now.