When Helen is walking with Dan to the car after he was shot her hair is flipped up in the back, but as soon as she gets in the car her hair is turned under.
When Dan pays Lt. Nelson the money he owes for the watch he counts out $100 in cash. But he only owed $99 for the watch as he had already put $1 down for it at the jeweler's.
When the lawyer is sitting in his car talking to Dan and Helen at the Santa Monica pier the reflection of one of the camera crew is visible in the driver's three-quarter window.