Continuity mistake: While fishing, Mr. Peabody hooks a mermaid who is swimming underwater. When he reels her in and she leans over the edge of the boat, her hair is completely dry and perfectly coiffed.
Revealing mistake: When Mr. Peabody is fishing, it is obvious that he is in a boat on the floor of a studio. Rear-screen projection is used to show the ocean behind him, but while he is standing in the boat and trying to reel in his catch, the boat is absolutely motionless.
