Mr. Monk and Little Monk - S4-E8
Factual error: In the flashback where Monk is explaining how the money was stolen, the principal finds the 5 dollar bill he wrote "good luck" on and holds it up for everyone to see. The bill he holds is a 5 dollar bill which was released in 2000, with the enlarged Lincoln. The flashback takes place in 1972.
Mr. Monk and Little Monk - S4-E8
Factual error: When Monk is talking to Sherry about the painting in the art gallery where the painted woman was going to kill her husband, he says that she has a bruise on her left eye. But the bruise is actually on her right eye. While it is viewable that it is on Monk's left, he would not make that mistake.
Mr. Monk and Little Monk - S4-E8
Continuity mistake: In the flashback scene of the kids in the school hallway, the autographed photo of Patty Duke disappears and reappears twice on the inside of Little Monk's locker door as the camera angles change.
Mr. Monk and Little Monk - S4-E8
Continuity mistake: When the kids are standing in front of the lockers, one of them is holding Monk's clarinet. The position of the instrument in his hand keeps changing between shots, from bell-up to bell-down, then bell-up again.
Mr. Monk and Little Monk - S4-E8
Continuity mistake: After the principal takes the stolen money, he shows the $5 bill he wrote on. But in the close up, the bill changes and so do the way the fingers are positioned.
Mr. Monk and Little Monk - S4-E8
Continuity mistake: When Monk is doing the summation for the present-day case with Sherry's ex-husband sitting in the chair, at first you can see that the painting is directly behind him. However, shortly thereafter during the summation, the painting has somehow shifted to the viewer's left and is no longer directly behind him. While it's plausible that someone could have moved the painting, it's just not believable since less than a minute has passed. Besides, would Lt. Disher (he was closest) really take it upon himself to move evidence?
Mr. Monk and the Secret Santa - S4-E9
Continuity mistake: In the beginning scene it shows someone injecting a liquid, with ease, into what appears to be a corked wine bottle. Then around the 13-min mark you see the Captain re-gift the bottle and when the person opens it, it's a pull cork with a hard top, something a needle would not easily go through. (00:00:10 - 00:13:23)
Mr. Monk and the Secret Santa - S4-E9
Continuity mistake: When Alice confesses to the murder in her kitchen, a large green plastic bowl that's been sitting on the counter disappears between shots. (00:38:05)
Mr. Monk and the Secret Santa - S4-E9
Continuity mistake: When Alice is in Stottlemeyer's office and Stottlemeyer can't find Terry's present, Alice says, "But what about..." indicates the bottle of port, and then drops her arms to her sides. In the next shot (when we see Alice from the back), we can tell by the position of her elbows that her hands are not at her sides, but in front of her.
Mr. Monk Goes to a Fashion Show - S4-E10
Revealing mistake: The fan letter Monk wrote to shirt Inspector 8, shown in close-up where it hangs on her work station wall, consists of the same paragraph printed out twice. (00:06:45)
Mr. Monk Goes to a Fashion Show - S4-E10
Continuity mistake: When the fashion designer draws a sketch on the newly painted wall, the drawing changes between shots, from four lines to about seven.
Mr. Monk Bumps His Head - S4-E11
Continuity mistake: When Cora goes upstairs, her cat is curled up asleep in a chair. In the next, close-up shot, the cat is awake and sitting at the edge of the chair cushion, looking up at Monk with its front feet hanging over the side. When the shot cuts to wide angle again, kitty is instantly back in his original position, snoozing far from the edge and curled up against the pillows. (00:32:45)
Mr. Monk Bumps His Head - S4-E11
Other mistake: The diner Monk enters to eat something after the truck driver gave him five bucks is the same diner that Christie and Sharona are waiting in to meet Monk after work in the episode Monk and the employee of the month. But while this episode is said to be in Wymington, the earlier one is set in San Francisco.
Suggested correction: This is trivia at best. While the set may be reused, it's not meant to be the same diner. It might be a chain restaurant so they look similar, but the seats inside are different.
Mr. Monk and the Captain's Marriage - S4-E12
Continuity mistake: When Stottlemeyer goes to open the window in his house, the position of his body (especially his right arm) changes between shots. (00:07:50)
Mr. Monk and the Captain's Marriage - S4-E12
Continuity mistake: In the hospital scene, the items on Gerald's tray change positions several times between takes. (00:27:00)
Mr. Monk and the Captain's Marriage - S4-E12
Revealing mistake: In their efforts to hide Gerald's pet mouse from the hospital staff, Randy and Natalie toss the rodent back and forth and alternate hiding him in their pockets. But every time he's tossed, Devo the Mouse gains weight. In fact, Devo's (stuffed?) stunt-mouse double is at least twice Devo's actual size. (00:27:00)
Mr. Monk and the Captain's Marriage - S4-E12
Continuity mistake: While at the crime scene in the junkyard, Monk is trying to explain things, but is unable to concentrate because one of the stacked junked cars still has a headlight in it. Frustrated, the Captain shoots the light out so Monk can continue, but as the screen pulls back the headlight is still unbroken in the car.
Mr. Monk and the Big Reward - S4-E13
Continuity mistake: During grocery checkout, the vegetable oil keeps shifting around between shots, from next to the clerk to behind the cereal. (00:06:00 - 00:07:00)
Mr. Monk and the Astronaut - S4-E14
Audio problem: When the astronaut is speaking and we hear "I made a mistake, Captain. Five years ago," his lips don't match what we hear him saying. (00:11:10)
Mr. Monk and the Astronaut - S4-E14
Continuity mistake: When Monk is describing the laser pointer incident to Dr. Kroger, the doctor closes his black folder and puts it on the arm of his chair. In the very next shot, it's back in his lap, and he again closes it and places it on the chair arm. (00:25:00)