A Cowboy Episode where Castle and Beckett go under cover as newlyweds at a Wild West-style resort to investigate a murder.
Tropes that appear in this episode:
- Affably Evil: Despite being an unrepentant and occasionally smug thief and killer, the episode's culprit is a cordial and accommodating host who loves the Old West and compliments Castle for being brave enough to try and stop his escape.
- Almost Dead Guy: The killer poisoned Whitney several hours before The Teaser, and the episode begins as the emergency team struggles to save her. She says that someone did this to her and "Diamondback" (referring to the ranch she came from) before dying.
- The Atoner: Dagmar felt so guilty about agreeing to cover up his best friend's murder in exchange for a fortune in gold that he looked after his friend's girlfriend and daughter for the rest of their lives, and manages a foundation sending poor kids to the best schools.
- Automaton Horses: Subverted when their horses spook at the sound of gunfire.
- The Bartender: Castle lampshades that western barkeeps tend to be affable sources of invaluable information, and the whiskered man at the Diamondback saloon proves Castle right. He also snarks at Castle for using a Hurricane of Euphemisms for whiskey instead of just saying whiskey, and later ducks below the bar right before the climactic showdown.
- Berserk Button: James, the guy Whitney used as cover by claiming they were having an affair, was not having an affair with her and is so upset that he uses the cover of the high noon shootout to drag Castle outside and threaten to beat the shit out him.
- Big Damn Heroes: Beckett shooting Grady.
- Blasting It Out of Their Hands: Beckett shows up and shoots the gun out of Grady's hands before he can shoot Castle.
- Bridal Carry: Castle carries Beckett across the threshold of their room this way. Unfortunately the mood is ruined when they see how tiny the bed is.
- City Slicker: Castle, of course.
- Dead Man's Chest: When Castle opens the US Treasury box, he finds Clyde's remains stuffed inside instead of gold bars.
- Disappeared Dad: Whitney's father was a treasure hunter who abandoned her mother before she was born in order to look for the Peacock Brothers' treasure. After finding the treasure, he was killed by the culprit during a dispute over what to do with it. When Whitney showed up to look for the treasure and her father, the culprit killed her too.
- Doomed Predecessor: The team find a picture of Whitney's father Clyde enclosed with letters talking about his quest to find a gold stash that long-dead outlaws stole. Castle and Beckett try to find the gold themselves, partially to solve Whitney's murder and partially because of Castle geeking out at the idea of finding Wild West buried treasure. When Castle and Beckett find the outlaws' cache, the gold is gone and Clyde's body (recognizable by his hat) is stowed inside the trunk that the gold was kept in.
- Failed Attempt at Drama: Castle tries slamming his way through the swinging doors of the saloon, only for them to slam back into him.
- Gay Cowboy: Tobias is a Camp Gay cowboy tourist.
- Gene Hunting: At least part of the reason Whitney visited Diamondback before her murder was to find out information about her treasure hunter father (who disappeared while her mom was pregnant).
- Greater-Scope Villain: Well over a century before the episode begins, the Peacock Brothers stole millions in gold and kidnapped a Native American boy who they forced to guide them to a good hiding place for their money (although they did let him go afterwards). However, they were killed by lawmen shortly after the robbery, and the search for their treasure during the episode is the reason for the murders.
- The Gunslinger: James Grady.
- I Resemble That Remark!: Castle suggests they investigate like writers because Beckett can't just flash her badge.Beckett: What, we procrastinate and make things up?
Castle: NO. Well, yes, but NO. - Innocently Insensitive: Martha starts gushing about the sunset ceremony (with doves) while Ryan, Esposito, and Lanie sit right next to her, seething.Alexis: Uh, maybe let's not rub it in? Let's go get you another drink.
- Literary Allusion Title: To Once Upon a Time in the West.
- Lost in Translation: The key to discovering the location of the gold. A Yavapai word mentioned in one of Clyde's letters was assumed by treasure hunters to mean "river," but the alternate translation of "stream" was more accurate, as the treasure turned out to be hidden in an abandoned mine near a dried-up stream.
- Mood Whiplash: Lanie chews Beckett out about how she has been dieting for months to fit in her bridesmaid dress and now Beckett goes and jumps the broom without even telling her? They're going to a restaurant, Beckett's paying, and they're ordering all the desserts! "Ooh, now come here, girl!"
- Oh, Crap!: Castle opens the bathroom door of their bunk room to find a naked Tobias behind it, immediately shutting it again.
- Outlaw: Train Robbers: The Peacock Boys
- Revolvers Are Just Better: Castle buys himself and Beckett matching six-shooters.
- "Wanted!" Poster: The Peacock Boys (train robbers from 1893).
- What Happened to the Mouse?: Dagmar (AKA Dutch) was best friends with Whitney's father and was present at his murder. He agreed to keep it secret in exchange for half the loot. Conspiracy after the fact, but we never hear about what happened to him. Given his situation (very poor at the time, looking at a fortune in gold, faced with a killer, and that he took care of his friend's girlfriend and daughter for the rest of their lives, manages a foundation giving college grants to disadvantaged children), he makes a very sympathetic criminal, so it makes sense.
- What the Hell, Hero?: Ryan, Lanie, and Esposito are pissed as hell that Castle and Beckett eloped and they weren't invited.
