Continuity: In the lumber yard, Randy shows a rare streak of genius by knocking out the bad guy with a 2x4 shoved through a stack of boards. When the 2x4 strikes Ringel, it stops its slide protruding about six inches from the stack. When the camera angle changes for the very next shot, the 2x4 is suddenly sticking out more than a foot.

Continuity: Ringel closes the blinds, then turns and walks away from the window. After a brief shot of Monk and Marcy, Ringel turns and walks away from the same window again.

Deliberate "mistake": It's out of character for Monk, a chronic stickler for details, not to correct an error, especially one relating to his own life. Marcy's diorama for "Mr. Monk & the Three Pies" includes Natalie, who wasn't around yet when "Three Pies" occurred. The doll should be of Sharona, not Natalie, but since that would ruin the ensuing joke, Monk was allowed to overlook the mistake.

Continuity: Near the end, when Ringel pulls a gun on Monk and Marcy, he reaches over and closes the venetian blinds. There's no gap in the shuttered blinds when he walks away from the window. Then there is. Then there isn't again.

Factual error: While the police are investigating the murder at the start of the episode, there is no sheet over the body or tent to cover the body. Being they are on a beach it would make sense to cover the body from any small debris or sand blowing onto the body. The sun is also shining brightly. I don't think the heat would help the coroner with the autopsy especially since it's murder.

Plot hole: There is a dead body on the beach, police all around and none of the public are even curious at the crime scene. There is quite a number of people at the beach and only a few people even take a glance at the body which is additionally uncovered. If there was no one around then it could be understandable, but the fact that no member of the public is even trying to look or even upset by this is just impossible to believe.

Continuity: A little white pillow on Natalie's couch falls over when Monk gets up, then rights itself again when he's in the kitchen.

Continuity: While Monk and co. question Vicky's roommate, two throw pillows behind her on the couch shift their orientations several times from shot to shot. The larger one also moves from the couch corner to a spot behind the woman's left arm and then back again.

Continuity: In the mausoleum, the bald man asks Monk and Natalie what happened to the cremation urn name cards, and bends to pick one of them up from the floor. There are no cards on the table when he does this, but in the next shot, four cards have appeared on the table out of nowhere. A short time later, they've all disappeared again.

Continuity: The shape of the first ring Randy draws on the TV screen changes from an oval to a circle and then back to an oval between takes.

Continuity: When Monk and Dr. Kroger (RIP) are in the session and Monk ask Dr. Kroger where he got his watch, Dr. Kroger puts his arm on the arm of the chair and his hand across his mouth. From the back, he has his hand on his cheek, but from the front again it is back on his mouth.

Revealing: When Monk, Natalie, and Joey are fighting on the roof, the end of the metal pipe in Joey's hand wobbles around a lot, as if the pipe is made of rubber.

Continuity: At the end, the unconscious Cousin Joey changes positions on the roof. Though no one's touched him, he somehow shifts from lying curled on his side to flat on his back.

Continuity: Monk drops the harmonica onto the coffee table, and it lands in a horizontal position. Monk doesn't touch it again, but it moves to a diagonal orientation and then back to a horizontal one between takes.

Continuity: When Monk is trying to overcome his fears with Natalie and Julie's help, the blue pillow on the couch beside him alternates from lying flat to sitting upright, without being touched, throughout the scene.

Revealing: During the fight between Max and Paulie, the stunt double for Paulie is easy to spot - he has a full head of dark hair, whereas Paulie is gray and largely bald on top.

Continuity: Gulliver makes a bet with Monk and puts $50 in bills on the bar. When Monk puts down a $50 bill to match the bet and slides it across the counter, Gulliver's money has changed positions, rotating 90 degrees without being touched.

Factual error: [SPOILER ALERT] At the end of the episode, it is revealed that the mysterious cab driver had corneal transplants to repair damage to her vision from Retinitis Pigmentosa. RP is a defect of the retina, in the back of the eye, which accumulates pigment, losing its photoreceptivity, resulting in vision loss. A corneal transplant will not restore vision to someone with RP.

Continuity: At the end, the glass of egg nog Julie and Natalie leave on the floor disappears after they stand up to talk to Monk.

Plot hole: This episode's entire story line takes place in the six days before Christmas (Dec. 19-24). "Bad Santa" is shot in the right shoulder on the 19th, sustaining a wound serious enough to require wearing a sling for the next several days. Yet at the end, a mere few days later, he's recovered enough to have a knock-down-drag-out fistfight with Monk, wielding a knife and throwing powerhouse punches with his wounded arm as though no injury had ever occurred.