Night of the Headless Horseman - S3-E11
Visible crew/equipment: When Nate Findley rides his horse the actor's stunt is very noticeable in the wide shots.
The Corpse Flew First Class - S3-E12
Factual error: As the airplane is coming in to land at Heathrow, there is an establishing shot of the wheels down, and in the background there are cars on the road, but driving on the right, wrong for the UK.
Crossed Up - S3-E13
Continuity mistake: When the crime is solved Jessica shows her emergency calling button. The way she holds it changes between shots.
Crossed Up - S3-E13
Continuity mistake: When Grady grabs the diary it swaps between closed or open depending on the angle.
The Bottom Line Is Murder - S3-E15
Continuity mistake: When the cop picks up the dirty ashtray he blows the ash away. In the close-up the ashtray is spotless as if it had been wiped with a cloth or if it were brand-new. First of all, no ash blew away, and second of all, a mere puff couldn't have cleaned it the way it looks.
The Bottom Line Is Murder - S3-E15
Visible crew/equipment: When Jessica rides in the car for the first time, the structure of the filming equipment is reflected on the hood.
Factual error: The whole episode is run as if based in the UK, and yet the script has obviously been written by an American. The UK does not have autopsies, it has post-mortems. The UK does not have a trunk (of a car) it has a boot.
A Very Good Year for Murder - S4-E17
Visible crew/equipment: After Tony is cured he exits toward his car. A big screen used for lighting is reflected on the side of the car.
Plot hole: When Jessica is arrested for the murder of the enemy agent. Her purse is confiscated. It was reported stolen by Michael Haggerty. But throughout the whole show none of the cops looked at her ID. Besides that she's a famous women and someone at the police station would definitely know who she is.
Visible crew/equipment: When the sheriff and the mayor meet at the fix-it shop, the filming crew plus the boom mic pole are reflected on the side of the red car.
Revealing mistake: All the shots of snow falling, mainly when Gunnar is about to be killed, are a very obvious crappy footage of flakes falling projected over the footage of the show. Not a single flake falls on the objects nor the people.
Something Borrowed, Someone Blue - S5-E9
Revealing mistake: When the corpse lies on the bed the pad under the clothes where the thermometer is stuck protrudes.
Something Borrowed, Someone Blue - S5-E9
Audio problem: Whenever someone is walking on a rug the sound we hear is of footsteps on a tiled floor.
Something Borrowed, Someone Blue - S5-E9
Continuity mistake: In the kitchen the police officer loosens his tie, but from the side shot it's still tight.
Fire Burn, Cauldron Bubble - S5-E13
Factual error: The only instances of "witchcraft" or "witch trials" in America were in Salem, Massachusetts. There were none in Maine or anywhere else. The Salem witch trials spanned 15 months, from February, 1692 to May 1693. Over 200 people were accused of witchcraft, but only 30 were found guilty. Of the 30, 14 women and 5 men were executed by hanging and one man, Giles Corey, was executed by "pressing." Another five died in jail, but none were burned at the stake, which was a punishment unique to Europe.
The Sins of Castle Cove - S5-E17
Visible crew/equipment: When the hairdresser buys a lot of books and leaves in her car, a huge screen and scaffold are reflected on the rear window.
Trevor Hudson's Legacy - S5-E18
Visible crew/equipment: When the woman picks up the hitchhiker the filming equipment is reflected on her car.
Trevor Hudson's Legacy - S5-E18
Revealing mistake: There are 2 scenes involving Jessica inside a car. In the first one the car drives calmly as seen from the outside shots, but from the shots inside the car is speeding. When the episode is about to end the car speeds to the police station and now the exact same projection is played, though this time it makes sense.
Mirror, Mirror, On the Wall (2) - S5-E22
Other mistake: When the sheriff finds the apple, the bitten side has a fresh white colour, instead of the brown colour it should have after the many hours passed.
Mirror, Mirror, On the Wall (2) - S5-E22
Continuity mistake: When Eudora arrives at Jessica's home to apologise, she's wearing a pair of gloves. A shot later, the gloves have vanished.