Other mistake: Following the accusation against the sheriff, the confrontation between the Mayor and Jessica is marred by a visible technical glitch. A negative-style overlay runs through the scene, including a light flare above the Mayor's head, a thick black line across the frame, and a whiteboard intermittently superimposed over the image.
Continuity mistake: When the mayor returns the sheriff's badge, his grip on it changes between shots.
Continuity mistake: When Mrs. Hellman grabs the coffee mug, her grip alternates between holding it by the base and by the handle from shot to shot.
Visible crew/equipment: Immediately after the sheriff hands over his revolver, the moving boom microphone becomes visible as it is reflected in the map behind the mayor, below the words "Cabot Cove." (00:25:22)
Funeral at Fifty-Mile - S1-E22
Continuity mistake: When Jessica walks from the house to the barn at the end, she is wearing knee high brown boots. By the time she reaches the barn they have been replaced with court shoes.
Revealing mistake: When the first scene at Emma's hideaway was shown, obviously the two characters Emma and Jessica were filmed seperately on the couch and then the film was put together (as both are played by Angela Lansbury). However Jessica did a lot of moving while she was talking, so Emma was looking straight across at where she had been, despite her bending down while she talked.
Audio problem: When singing "Goodbye little yellow bird" Emma blows a kiss to Oliver offstage, but she is still singing the song when she is blowing the kiss. Although it's possible she was pretending as it was part of the act, her voice wasn't even muffled by her hand.
Continuity mistake: When Emma was almost hit by a car she jumped up onto the edge of the wall and then back down onto the floor. When she landed she was facing the theatre door, but when Oliver came of the door and the shot changed, she was facing away from the wall. This happened in the transition from stunt person to Angela.
Tinker, Tailor, Liar, Thief - S8-E15
Revealing mistake: In the second close up shot of Nigel Atkins lying dead, after Jessica drops her Harrod's bag in the chair, it is obvious he is still alive as you can see his pulse on the side of his neck.
Factual error: At the end of the episode after Wayne is shot, there is a brief shot of the outside of the hospital where he has been taken. The sign outside the hospital says Dalesboro, Ohio. Why would someone shot in coastal Maine end up in a hospital in Ohio?
Deadly Lady - S1-E2
Revealing mistake: When Howard Duff's two daughters enter the police station to identify his body, the cop pulls back the blanket. Howard's eyelids are moving even though he is supposed to be dead.
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.
Funeral at Fifty-Mile - S1-E22
Visible crew/equipment: After Jack's graveside service, Jessica, Mary, and Art walk back to the red pickup, and while they're standing there talking, the mic pops up into view in front of Mary. (00:04:40)
Visible crew/equipment: When Roland's chauffeur opens the door, set lights are reflected in the window. Wider shots of the location show no lights matching those reflected in the nearby glass, confirming that the reflections originate from the filming equipment rather than from any practical sources on set. (00:25:26)
One Good Bid Deserves a Murder - S2-E17
Continuity mistake: The first time Jessica is shown asking for her room number, she asks for room 812. Later in the episode she asks for room 810.
The Murder of Sherlock Holmes - S1-E1
Continuity mistake: When Jessica's publisher at the beginning of the party holds her hand and kisses it, he is holding her hand in different ways in the separate shots. (00:18:20)
The Murder of Sherlock Holmes - S1-E1
Continuity mistake: Mr. Giles holds the telephone as he interrogates the private eye, who answers in a rather defiant way to the threat of "the local constable" getting involved. So Giles puts the receiver down, but notice that in the first shot he is passing it from the right to the left hand. In the close-up it is the right hand to hang up, though. (00:23:15)
The Murder of Sherlock Holmes - S1-E1
Continuity mistake: During the scene at the train station, Jessica's nephew introduces to her Kitt Donovan from the publishing company. Just as he says "in public relations", a man pops in the foreground - it is an extra that walks out of the rail car. In the reverse shot that follows, the same extra is only then coming out of the train. (00:09:35)
The Murder of Sherlock Holmes - S1-E1
Continuity mistake: Episode 1-0, "The Murder of Sherlock Holmes"; Mr. Giles opens the door of the antechamber of his office, finally putting an end to Jessica's long wait. Grady right away at the first click of the lock takes his hands off his pockets and tidies up his sleeves. But in the next shot when Grady actually enters and talks to the secretary, Grady is still with his hands on his pockets repeating the gesture. (00:10:10)
Another Killing in Cork - S11-E20
Continuity mistake: In the opening exterior shot of the train, it has at least six brown and green carriages. However, in the next exterior shot, the train is made up of three brown and cream carriages.
Answer: In a flashback scene, it was shown that he had a violent temper, so it stands to reason that he finally killed her in a fit of rage.