Workers in a dead letter office open up boxes -- and discover nasty human remains. "That's it, I retire," says the older worker. "Welcome to the U.S. Postal Service, kid." CUT to Booth and Bones, who continue to hunt for a house while eating lunch at the diner. Just then, Booth's grandfather enters. "It's not me, Seeley," pops says. "It's you're dad." Turns out Booth's dad is dead -- liver failure. Booth reacts like he has just been told it's a Tuesday. "Take care of him," a worried pops tells Bones after Booth exits.
CUT to the dead letter office, where the team pours over multiple boxes containing remains. "I wonder if the killer does gift wrapping on the side," Camille quips. Back at the lab, Camille and Clark assemble the boxes in the shape of a human. They remove the remains using a fancy laser (Hodgins's idea). Agent Shaw, in the meantime, comes to Booth with news: the labels on the packages were created to end up at the dead letter office and the packaging was very professionally done. Angela scans the QR code on the labels and reveals that the boxes were shipped from a location in Maryland.
So B&B hit the road. "I really am OK, so you don't have to worry about me, OK?" Booth tells his life partner. "I am at peace with this." Bones isn't buying it. Clark calls with news: the victim was a shipping company employee named Oliver Lawrence. Not only that, but extensive testing with ancient weapons (Hodgins's idea) has revealed that the victim was killed with a guillotine. Sure enough, B&B arrive at the shipping company and quickly discover a modern-day guillotine designed to slice stacks of paper.
Booth interviews the manager, who reveals that he and three former employees bought a lottery ticket together and won $60 million. The three employees promptly quit. Left out of the group were Oliver and Tony, who still works the front desk and showed off his Buddhist necklace made from human bone (actually a fake, Bones points out). Later, Agent Shaw studies the winning number and discovers that they are a combination of Oliver's birthday, street address, and high-school basketball number. Her theory: one person killed Oliver for the ticket and the others found out, trading silence for a share.
Booth and Sweets bring in all the former employees/lottery winners, who say they only want to help ... but it seems awfully clear that they're hiding something. Booth then gets a call from Angela, who has examined the shipping orders from the day Oliver died. Turns one of the lottery winners, Ralph, printed out the labels on the remains-filled packages. Ralph denies killing Oliver, but admits that Oliver was a fifth winner. "We were saving his share until he came back," Ralph says. "That is the truth. I swear." Ralph then claims that everybody used his code on the printer because his code was "1234."
Back at the lab, Clark and Bones examine the victim's bones and discover that Oliver was engaged in a struggle before he died. He was struck by some sort of object. Later, Booth cooks a spaghetti dinner while pops goes through the paperwork concerning the death of Booth's dad. Booth is dismissive. "Good or bad, he was my son," pops says. "I'm a little disappointed that you don't see the hurt I'm feeling." Booth apologizes. Says pops: "Seeley, we're family. We've got to get through this together." Booth agrees, and promptly signs all the paperwork as he was apparently named the executor.
CUT to the lab, where Camille and Hodgins continue to examine the body parts. They discover that the victim had a bone growth on his left hand. Angela, meanwhile, examines images from the shipping company's copy machine. She finds that someone copied a woman's buttocks. Next to the buttock's is a male hand with a bone growth. Looks like the victim and a lady were doing the deed on the copier and accidently hit the "copy" button. "Now we just have to figure out whose tush this is," Angela says. Angela matches the size of the buttocks with the buttocks of lottery winner, Sheila. It's exact.
Sheila is brought in for questioning ...and she brings her lawyer, who refuses to let his client talk. Still, Sheila, a married woman, can't resist after being confronted with copy-machine evidence that she slept with Oliver. "I'm a slut, not a killer," she snaps. Booth wants to know where her husband was the night Oliver died. She doesn't have an answer. "I hate my job," the lawyer mutters. Later, pops tells Booth that he's leaving town -- but wants to read Booth a letter that his father wrote. "Just shut up and listen," pops snaps. The letter is full of regret, saying that he loved Seeley and Booth's brother. Pops then gives Booth a wooden box left to him by his father. Booth doesn't want to open it.
Clark, meanwhile, has discovered that the blows to the victim's bones were made with an industrial tape gun. Angela checks the models used by the shipping company and discovers a match with a certain tape gun. Better yet, the marks indicate that killer was left handed. And which of the lottery winners was left handed? Turns out that Sheila's husband, Hugh, is a lefty. But when shown the evidence that Sheila was fooling around with Oliver, Hugh storms out of the interrogation room on his lawyer's advice -- the same lawyer, by the way, that was representing Sheila. Back at the lab, Hodgins finds a sliver of a material jammed into the packaging. "It's bone," he says. Bones discovers, however, that this bone did NOT belong to the victim. Instead, it comes from a "Buddhist necklace made of human bone" -- or at least a fake one.
So Booth and Agent Shaw bring in Tony. Tony quickly admits that he was dealing drugs and shipping them out from the store at night after everyone had gone home. Agent Shaw then presents Tony with the chip of bone from his pendant. Turns out that Oliver discovered Tony was shipping drugs and they got into a fight. "I have been non-violent for over 25 years," Tony admits. "I lost it for five minutes." Killer found. Case closed. But not the episode. Later, Bones tries to get Booth to open up about his father. "For the time being, we're sharing our lives and that means you can't shut me out, Booth," Bones says. So Bones makes Booth open the box from his father. Inside is a Purple Heart, a Father's Day card from Seeley, and pictures of the two together from long ago.
Booth tears up, especially when he finds ticket stubs to the World Series game they attended together -- their one perfect day. Finally, Booth smiles.