A woman's frozen body is discovered, covered in a garment bag and tangled in the rebar of a construction site.
Having gotten the early morning phone call about the body, Beckett straps on her gun, slides on a man's watch and clips her badge to her belt. Lastly, she slips on a silver necklace with a ring on it and tucks it way under her shirt so it's unseen.
Beckett arrives at the construction site to discover Castle already there. Lanie is busy examining the body in the crossbars. She won't be able to get any prints or DNA until the body thaws, so Beckett has a CSU Tech take close-up pictures to run through their missing persons database. Castle is excited to see how high tech the operation is.
Back at the precinct, Beckett shows Castle the missing persons "database" -- a large stack of files. It's a daunting task. As they go through the files, Ryan explains that he thinks the body had to have been kept close to the site. Castle disagrees and says, "It takes a long time for a body to thaw. Just like a turkey." As they start to go over this, Beckett gets a call -- Lanie has identified the victim.
Melanie Cavanagh, the victim, was killed by blunt force trauma to the head. Also, judging from the lack of frost and tissue degeneration, Melanie's corpse was likely stored in a freezer. And she's been missing for over five years!
Castle and Beckett learn that Melanie had been a runaway bride, disappearing for weeks at a time, which is why her husband, Samuel, waited a day after her final disappearance before calling the police. He thought Melanie had simply skipped town again.
Beckett and Castle decide to break the news of her body being found to Samuel. But when they arrive at his apartment, they discover Samuel doesn't live there anymore. In fact, according to the new tenant, Samuel Cavanagh was been murdered eight months before.
They run background on Samuel and discover he was shot outside a grocery store with a small caliber gun, his wallet and cash were missing. The couple's two children are now living with Melanie's parents in White Plains.
They arrive at the home of Ben and Julie Davidson to tell them the bad news. The parents are saddened but relieved to finally have answer. Even though Melanie had a troubled past, they were sure she never would have left her kids voluntarily. Still, Ben remains angry that Samuel waited a whole day before reporting Melanie missing and laments that the detective covering the case, Clay Sloan, didn't ask the right questions.
Beckett and Castle meet with Sloan, who is now a sheriff in New Jersey. He's not surprised Melanie was found dead, considering her history of drug abuse -- he had received reports of her in Philadelphia with a meth-head ex-boyfriend. Beckett notes that the reports came from Samuel's friend, Charles Wyler. Sloan counters that he had no reason to doubt Wyler's word.
They meet Esposito and Ryan at a storage facility. Esposito found a homeless guy who claims that the previous night he saw a heavy-set guy at the construction site pulling a large bag out of a dented yellow truck with "storage" written on its side. So Esposito and Ryan searched all the storage places on the West Side and found the one using yellow trucks.
Beckett and Castle head into the storage facility and speak with the owner, Albert Bolland. Bolland admits to dumping the body but says he found it in one of his storage spaces after the renter stopped paying. Because he thought the body was a mob hit, he didn't call the cops.
Bolland takes them to the storage unit, where they find a freezer containing remnants of the garment bag. Bolland says a guy paid the rent every six months in cash. The last payment had been made nine months ago -- two months after Sam's death.
At home, Alexis finds Castle staring into his freezer. He asks his daughter why anyone would stash a dead body in a freezer. Alexis figures it's because they were trying to hide it. But then why would they stop paying rent on the storage space? Alexis wonders if they stopped paying willingly or whether something stopped them.
Beckett and Castle visit Sam's best friend, Charles Wyler, at his store. He's surprised to hear Melanie's been found dead. He says it was Sam who told him Melanie was in Philadelphia with her ex-boyfriend, Kevin Henson -- he's who she always ran off to. If anyone would know what happened to Melanie, Henson would.
At the precinct, Beckett hands Montgomery a mug shot of Henson. It turns out he started serving a one-year jail term just after the last payment was made on the storage unit. And Henson had been out of jail when Sam got whacked.
Beckett and Castle head to prison to question Kevin Henson. He tells them Melanie did come to see him a month before her disappearance. She'd found out Sam was having an affair, so she wanted Henson to take her and the kids away and just vanish. Unable to make that commitment, he put her on a bus and sent her home and never heard from her again.
They visit Wyler again, who admits Sam was having an affair, but refuses to name the girlfriend. It's only after Beckett threatens to prosecute Wyler as an accessory that he talks -- he was sleeping with Elizabeth Forte, a co-worker at Sam's bank.
Castle and Beckett question Elizabeth Forte. She admits to having an affair with Sam, but claims she broke it off after six months. Sam had started asking what she would do if Melanie was out of the picture. When Melanie disappeared, Elizabeth broke it off with Sam. She never told anyone and now that Sam's dead, she didn't think it was important.
Later that night, Beckett stares at her murderboard, frustrated by her inability to figure out exactly how Sam killed Melanie. She now has a strong theory as to why Sam did it, but she can't prove it.
Beckett visits Castle at his loft. She tells Castle that she can't crack the case, but feels Melanie's family needs to know the facts. Castle, sensing Beckett is talking about more than this one case, suggests they try working backwards from the ending -- if Melanie was home taking care of the kids that day and never left the apartment, then she must have been killed there. But how did Sam get her body to the storage facility without being noticed?
At Sam and Melanie's old apartment, Castle and Beckett try to imagine what happened the day of the killing. Melanie and Sam were probably having an argument in the kitchen. Sam would have struck her on the head with a pan, fracturing her skull and killing her. He probably then would have hidden her body in the hallway bathroom. But how did he get the body out of there? Castle surmises Melanie must have already been in the freezer when Sam moved her from the apartment.
Castle and Beckett check the doorman's ledger and find a signature for the one delivery made that day. They then talk to the tenant who signed for it, Delores March. Even though it was five years ago, Delores remembers the delivery well, because she never ordered a freezer. By the time she straightened things out with the doorman, the deliveryman had already come and gone. She already had told all this to the detective investigating the case.
Beckett and Castle visit the company listed on the delivery ledger, where they discover trucks identical to the ones at Charles Wyler's store. Clearly, Charles Wyler helped his friend Sam move Melanie's body.
Wyler sits in the interrogation room, looking defeated. They've traced the rental of the delivery truck to him. So Wyler comes clean: Sam called him to the apartment that evening; there, he found Melanie in the tub, stuffed inside a body bag. Wyler agreed to help Sam with a cover-up because he felt bad for their two kids. So he rented the truck and the storage space, and made regular payments on Sam's behalf.
As the pair is wrapping up the case with Captain Montgomery, Castle notices a telling omission in the original report -- Detective Sloan didn't list an interview with Delores. And if Sloan were only investigating a missing persons case, as he claims, why would he talk to the neighbor about a freezer delivery?
They pay another visit to Delores, who reveals that the detective spoke to her not five years ago but last year. She remembers that he was older, wore plain clothes and walked with a limp. Castle and Beckett realize that she's describing Ben Davidson, Melanie's father.
Beckett and Castle sit inside Beckett's car in front of the Davidson home. They can see Ben Davidson through the dining room window, setting the table with the help of his granddaughters. Castle suggests they leave it be, but as she opens the car door, Beckett notes that, unlike a novelist, a cop doesn't get to decide how a story ends.
At the station, Ben admits that, upon interviewing Delores about the freezer, he came to the same conclusion they did: Sam killed Melanie. He decided not to go to the police because they didn't have a body at the time, and he knew Sam's defense lawyers would have put Melanie's past on trial. While not admitting to Sam's killing, Ben says he could understand why a father might want to seek revenge. He then asks to see a lawyer.
Afterward, Beckett tells Castle that, when she was young, her mother had also been killed. The cops ruled it the result of gang violence, and just like in Melanie's case, they never looked outside the box for a more complicated answer. Beckett's father took it pretty hard, but he's been sober five years now. So Beckett wears her father's watch to remind herself of the life she saved and her mother's ring to remind herself of the life she lost.
At home, we see Beckett run through her morning routine in reverse, stashing her gun and badge, and putting away her father's watch and mother's ring inside the jewelry box -- a photo of her father and mother in happier times atop the box.
Meanwhile, in the precinct record room, Castle sits down at a table with a Johanna Beckett's case file. He opens it and begins to read it.