Visible crew/equipment: You can see a rope visible when Charlie is hanging from the hotel roof.
Continuity mistake: In the prosecuting attorney's speech in the first courtroom scene, the judge's house of cards is no more than 2 levels high (a base level with a peak) [0:2:20]. In the close-up shot of the judge, the house of cards changes to 3 levels high (2 base levels and a peak)[0:2:35]. When the scene focuses back on the prosecuting attorney, the house is back to two levels of height[0:2:39]. (00:02:20)
Visible crew/equipment: In the VHS edition, one can see a reflection of a boom mic in the painting above the staircase landing as Ann-Margret goes up the stairs to Jack Lemmon's bathroom, and again when she comes down. (02:51:30)
Other mistake: In the second wedding scene, as Don Pedro and Claudio are walking up the aisle you can see an extra jumping over the benches on the left-hand side of the screen. He clears the first one, but trips on the second and falls flat on his face.
Continuity mistake: At one part in the movie Christopher Lambert points a revolver at a gun dealer. When they cut back he is pointing a semi-automatic pistol. This is done three times.
Audio problem: In the beginning, when the Blues are at the wedding and Jeff is taking the baby from Jane he says "Dance with me" but his lips don't match.
Continuity mistake: When Arnie and Jay arrive at their grandmother's candy store to stay with her, their Aunt Bella is making ice cream sundaes for them. Watch the whipped cream and cherries on top of both sundaes, they go from melted to fresh again between shots.
Revealing mistake: In the scene where Rick returns from the lab with the macaroons, it is obvious that the worm man is only in half of his costume. He's wearing black pants and shoes and sitting on a stool.
Revealing mistake: The soldiers on the beach were armed with M-16 rifles. The movie period was 1962, during the Cuban Missile Crisis. The M-16 and M-16A1 were not manufactured until 1964.
Suggested correction: Just watched Matinee again after reading this. I saw M1 carbines, M1919A4 and M2.50 cal machine guns and M14 rifles. There are no M16 series weapons in this movie.
Visible crew/equipment: When Carol and Ted are waiting in the car, during the shot where it is raining, you can see the reflection of a crew member on the window. He tries to stay out of sight, but you can still see him moving.
Visible crew/equipment: When Doug is pitching his idea to Christian, they are outside on the terrace of the hotel. As Christian is walking inside, he walks past some windows and you can see the camera and the crew in the reflection.
Deliberate mistake: Towards the end of the film, Josh is playing a game in the park with Vinnie, and Vinnie asks "What's that?", to which Josh replies "Schliemann Attack." However, this dialogue occurs while the game is still in standard opening theory and before Josh has played the move that introduces the Schliemann Attack (pawn to f5).
Visible crew/equipment: When Rosie O'Donnell's dog is chasing the neighbor's cat, it it very clear there is a stuffed cat attached to the camera to lure the dog to follow.
Factual error: When Sharon is being driven by her Dad to the hospital to give birth to her baby ('Snapper'), they drive over a bridge on the River Liffey in Dublin to the south side of the city. However, the Rotunda Hospital, where she gives birth is on the North side of the city, quite a distance away from where they seemed to be headed.
Continuity mistake: After Miranda sings for the hotel manager, her guitar case closes and zips itself in a split-second.
Continuity mistake: When Sheela, Pru and their two dates leaves the house, Giddy is seen sitting upright by the table. When it cuts to a close-up of Giddy, she leans onto the table while resting her head on her hand. (00:38:05)
Revealing mistake: You can see the shadow of a camera and a microphone on Michael Biehn or Nicolas Cage back when they are fighting.
Revealing mistake: When Henry Mancini hands his conductor's baton over to the animated Pink Panther in the title sequence, he pushes it straight through the Panther's hand.
Character mistake: Detective Ferguson doesn't follow procedure and give Gloria her right to counsel prior to interrogation.
Continuity mistake: When Max chases the cat up the tree, in the close-up where you see Max's claws grow, the tree bark texture is different from the shots before and after.