Other mistake: When the camera looks at Paul Drake watching the recreation, the cameraman and equipment is reflected on the mirror housing.
The Case of the Sleepwalker's Niece - S1-E2
Revealing mistake: The carpets in the sleepwalker's house looked like they're unfolded tarps. There are noticeable folds in the carpet that looked as if a folded cloth had been unfolded but the creases were still there.
The Case of the Sun Bather's Diary - S1-E17
Character mistake: The reporter over the radio says Arlene Dowling is accused of murdering Frank Ballard, but the name of the murdered guy is George Ballard. Frank is her imprisoned father, Frank Dowling. (00:43:50)
The Case of the Hesitant Hostess - S1-E29
Factual error: Supposedly, heroin is being smuggled into the country in secret compartments in women's purses, but the quantity of heroin that could be concealed in such a way would be so small as to be very unprofitable for the smugglers.
The Case of the Lucky Loser - S2-E2
Visible crew/equipment: After leaving her husband at train station, Harriet takes a cab to meet a man at a cabin. After a few mins, she takes the man's car to go home. As she drives away, there's a reflection of a man, in suit with glasses (possibly the director) standing offscreen. (00:05:20)
The Case of the Pint-Sized Client - S2-E3
Other mistake: In an abandoned house, a 14-year-old boy finds a satchel filled with money taken in a holdup at a finance company. He uses $50 to buy a robe for his grandfather, then hides the rest of the money in his grandfather's house. During the trial of the grandfather, who is accused of being one of the holdup men, the police lieutenant says, "We found all the money except for $12,000. We conducted a second search of the home and found the rest of it." He should have noted that $50 was missing.
The Case of the Deadly Toy - S2-E27
Plot hole: Claire Allison spends the night in an upstairs bedroom in the Jennings' home. In the middle of the night, she opens a walk-in closet to get another blanket and finds a small printing press. Later in the day, Claire returns to the home, accompanied by Perry Mason, who tells Mr. Jennings that Claire has received threatening letters from Mrs. Jennings' former husband, who still has a key to the Jennings' home, and the printing press may have been used to address the envelopes. Mr. Jennings says, "We'd better investigate" and immediately goes upstairs and opens the closet, even though neither Claire nor Perry Mason said where Claire saw the printing press.
The Case of the Wayward Wife - S3-E13
Revealing mistake: Perry and Della step into an elevator but there is no line in the floor between the floor they are on and the elevator floor. It's continuous.
The Case of the Wayward Wife - S3-E13
Factual error: May buys a book for 4.95. Give the clerk a $10 bill but the register shows change of $5.15.
The Case of the Wandering Widow - S4-E6
Continuity mistake: Perry and Paul go to the park at ten o'clock at night but the sun is shining and casting shadows.
The Case of the Wandering Widow - S4-E6
Character mistake: As Mr. Morgan (Dean Harens) is being examined by the prosecutor he's also sitting in the gallery.
The Case of the Borrowed Baby - S5-E26
Continuity mistake: Mason takes the medallion back from the matriarch as he leaves her home. A little later the old lady shows up at Della's and shows the medallion to Della.
The Case of the Borrowed Baby - S5-E26
Continuity mistake: As Della burps the baby she has a towel over her shoulder one instant; in the next scene the towel is missing.
The Case of the Capricious Corpse - S6-E2
Revealing mistake: The murder victim is seen through the legs of a chair - just as the scene changes he blinks. (00:11:00)
The Case of the Fickle Filly - S6-E11
Other mistake: George Tabor parts his hair on his right side, however when Perry cross examines Mr. Tabor his hair is parted on his left and then reverts back to his right side. The two dots on his tie are one low and one high, they also switch. The negative must have been flipped.
The Case of the Laughing Lady - S9-E1
Continuity mistake: Professor Toby is shown in the background as someone in the audience is highlighted, but is supposed to be on the witness stand and appears there in the next instant.
The Case of the Cheating Chancellor - S9-E4
Character mistake: Paul Drake tells Perry the "speedometer mileage" of a murdered man's automobile is 63,192. Speedometers do not show mileage. He meant to say "odometer."
The Case of the 12th Wildcat - S9-E8
Other mistake: Perry, Paul and Della attend a Wildcats football game at the Los Angeles Memorial Coliseum. Stock footage shows a packed stadium. After the game ends, a close-up shows the three exiting the stadium along with several other people. The next scene takes place outside the entrance to the Coliseum. In a long shot, only two cars and six people are visible. In 1965, the Coliseum's seating capacity was 101,574. Where did everyone go?
The Case of the Runaway Racer - S9-E10
Other mistake: Pete Griston is test-driving a race car. When the car stalls, another driver crashes into him. Pete is thrown from the car and suffers a head injury. Several scenes show him with a huge bandage on the back of his head. His hair was not shaved. The bandage is on his hair.
The Case of the Sausalito Sunrise - S9-E19
Revealing mistake: Secretary Della Street answers the telephone in Perry's office and speaks briefly with the owner of an art gallery. She presses the "hold" button, then hands the receiver to Perry and says, "It's Mr. Clune." Perry and Mr. Clune have a lengthy phone conversation, even though Della never released the "hold" button.
