The Aztec Brooch
So why does Jo Ann (Barbara Bel Geddes) tell the white lie about the brooch? Joe is opening up to her and she to him, and she mentions that she has lied before but she's not a liar. It's right then that she says the brooch is special, and she gives it to him (a parallel to the teddy bear she "gave" to him before).
Is it just a quick moment of panic-- in this intimate moment, he asks her about the pin and she doesn't want to hurt his feelings, so she fibs? Or is it just an instinct-- she blurts out the story the Vincent Price character has told her about the brooch because she has let the idea become a romantic fixation in her head (in other words, she seems to lie only because she's so emotionally honest, blurting out that it means so much to her and forgetting where it came from)?