Continuity: When Clayton is discussing the lunch invitation with Hannah, the time on the kitchen clock jumps about inconsistently between shots.
Continuity: The first time Clayton Boone drinks ice tea with James Whale, Clayton drinks most of his glass at once. The next time we see Clayton, his glass is almost full again.
Continuity: When Hanna stands up to turn the TV off, she throws her napkin/towel on the small table in front of her. It covers most of the table, and also part of her plate (on the right side of the table). When she has turned the TV off and looks back at James, we see the towel lying neatly on the left side of the table.
Anachronisms: The Fiesta disc pitcher used by Hanna in the studio is the post-1986 yellow not the original yellow that would have existed in 1957.
Continuity: When Whale and Boone get caught in the rain they shelter under an umbrella. In one shot Whale's right side is completely drenched, in a following shot his right side is much drier.
Continuity: When James invites Clayton for some ice tea, by the time Clayton gets to the door the sweat and most of the dirt on his shirt have disappeared.
Continuity: When Clayton and Betty are by the car talking with the open car door between them, from one angle betty is seen with her left hand on her hip then shown from the reverse angle her hand is on top of the car door.
Continuity: During a meeting with James, Clayton has a drink in his hand. The end of one shot shows the glass in one hand while the beginning of the next shot shows it in his other hand.
Continuity: Before starting his line about James wanting "to draw him like a statue" Clayton tosses away his towel. James turns from the window and Clayton punctuates the end of his line by tossing his towel away again.
Revealing mistakes: The Eagle Globe and Anchor on Clay's lighter at the top of the movie is backwards.