You'll want to watch Castle Season 5 online to check out Rick Castle and Kate Beckett's first season as an official romantic couple, even if they do have to hide it from the NYPD.

Castle Season 5 Finale Photo
Watch Castle Season 5 Episode 24
"Watershed"
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Beckett reconsiders what she wants out of her job, and out of her relationship, in the Season 5 finale of Castle.

Carlos Bernard on Castle
Watch Castle Season 5 Episode 23
"The Human Factor"
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Why are federal agents trying to take over a case? That's the question on Castle this week.

Cute Castle
Watch Castle Season 5 Episode 22
"Still"
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Beckett's life is on the line on this episode of Castle after she steps on a bomb. Uh-oh!

Ryan and Castle Scene
Watch Castle Season 5 Episode 21
"The Squab and the Quail"
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Beckett is assigned to protect a billionaire on this episode of Castle, which prompts her to reflect on her relationship.

Something Amiss
Watch Castle Season 5 Episode 20
"The Fast and the Furriest"
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When a dead woman is found with claw like slash marks, Rick wants to believe Big Foot is the culprit on Castle.

A Bored Castle
Watch Castle Season 5 Episode 19
"The Lives of Others"
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Rick goes stir crazy when he's stuck at home and thinks he witnesses a murder in another apartment on Castle.

Kevin Ryan Photo
Watch Castle Season 5 Episode 18
"The Wild Rover"
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We learn a lot more about Ryan on this episode of Castle, as the detective goes undercover.

Castle, Beckett and Espo
Watch Castle Season 5 Episode 17
"Scared to Death"
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Castle and Beckett delve into an especially creeper case this week, as a woman dies... from fear?!?

Leading Castle Away
Watch Castle Season 5 Episode 16
"Hunt"
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We finally meet Castle's father on the conclusion of the annual two-parter. This is a major episode!

Dylan Walsh on Castle
Watch Castle Season 5 Episode 15
"Target"
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Dylan Walsh guest stars on this episode of Castle. It's the first of a two-parter.

Partners Fighting Crime
Watch Castle Season 5 Episode 14
"Reality Star Struck"
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Castle parodies The Real Housewives franchise this week, as a rising young reality star is killed.

Beckett vs. Bracken
Watch Castle Season 5 Episode 13
"Recoil"
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Senator William H. Bracken is back on Castle this week. He is linked to the death of a young woman.

Kelly Hu on Castle
Watch Castle Season 5 Episode 12
"Death Gone Crazy"
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The founder of an adult video franchise is found dead on Castle this week. Kelly Hu guest stars.

In a Bedroom
Watch Castle Season 5 Episode 11
"Under the Influence"
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A DJ is killed on this episode of Castle, forcing Kate and Rick to delve into the raucous world of New York's music industry.

Caskett at Home
Watch Castle Season 5 Episode 10
"Significant Others"
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Castle's ex-wife visits this week, causing a problem when she is forced to shack up with Castle and Beckett.

Kate & Rick's First Christmas
Watch Castle Season 5 Episode 9
"Secret Santa"
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When a man in a Santa suit and Kris Kringle ID is found dead in the snow, Beckett and Castle must hunt down his killer... all while preparing for their first Christmas together as a couple on Castle.

Castle Hiding Out
Watch Castle Season 5 Episode 8
"After Hours"
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Castle and Beckett bicker on this episode, only to be sent to retrieve the witness to a murder. From there, the couple goes on the run.

Beckett's Being Filmed
Watch Castle Season 5 Episode 7
"Swan Song"
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A film documentary crew decide to film Castle and Beckett as they investigate the death of a rock star. C Thomas Howell guest stars on Castle.

The Team Goes Sci-fi
Watch Castle Season 5 Episode 6
"The Final Frontier"
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Castle and Beckett find themselves investigating a murder at a sci-fi convention which has them dealing with crazy costumed fans and egotistical celebrities on this episode of Castle.

Castle The Suspect
Watch Castle Season 5 Episode 5
"Probable Cause"
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Castle is somehow linked to a murder this week. It involves a ritualistic killing.

Caskett Sighting
Watch Castle Season 5 Episode 4
"Murder, He Wrote"
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Csatle and Beckett plan a romantic weekend away on this episode. But it doesn't go according to that plan.

Castle at an Auction
Watch Castle Season 5 Episode 3
"Secret's Safe With Me"
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This episode of Castle brings a repossessed storage unit, treasure seekers and Manhattan socialites together following the murder of a woman.

Under Where?
Watch Castle Season 5 Episode 2
"Cloudy with a Chance of Murder"
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Beckett returns from her suspension this week, while WHNY's veteran weather girl is found dead and she and Beckett look into the crime.

Castle Season 5 Premiere Pic
Watch Castle Season 5 Episode 1
"After the Storm"
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Beckett and Castle deal with the aftermath of their hookup. Ryan and Espo are still in a fight as they chase down clues to help find Kate's shooter. The path leads the four of them to a powerful man in a powerful position. Find out who is our review.

With Rick Castle and Kate Beckett finally in a romantic relationship, you'll definitely want to watch Castle Season 5 online here at TV Fanatic. Rick and Kate figure out the fun and the pitfalls of being a couple when they have to hide it from everyone at the 12th precinct for fear that Rick will get kicked off the case. But trying to hide the truth from all of those detectives will be a definite challenge for the new couple. Rick and Kate can't seem to get away from murder, even when they plan a romantic getaway to his beach home in the Hamptons. A dying man falling into the pool definitely kills the mood. Later, Castle faces his scariest challenge when Alexis is kidnapped and taken out of the country. Help comes from a completely unexpected place when Rick's long, lost father appears out of the shadows to help. Later, as Kate begins to question where their relationship is headed, she's offered an amazing job in Washington D.C. Will she leave Rick and the 12th to take on this great new opportunity? Just when it looks like Rick might break things off, he pulls out a ring and proposes. You won't want to miss one romantic moment. Watch Castle Season 5 online here at TV Fanatic.

Castle Season 5 Quotes

The fact is that I admire your loyalty and hope you can feel that way for me someday.

Gates

That's going to leave a nasty scar. Every time you see it, think of me.

Beckett

Castle Season 5 Music

  Song Artist
Song Move That Ass (Get On the Floor) The Page Brothers
Call Me Maybe Carly Rae Jepsen iTunes
Song All I Could Think About Was You Robert Duncan