Just after Dexter is kidnapped by Liddy, Lumen walks out of the bedroom of Dexter's apartment and into the kitchen. As she does so there is a light brown leather purse lying flat on the bar stool at the end of the kitchen counter. As she walks past the purse it is suddenly sitting up, then again lying flat in the next shot even though she never touches it.
Just before Dexter gets out of his car to confront the person surveilling him, he puts the tranquilizer syringe in his mouth. But in the next shot, his mouth is empty and the syringe is in his hand.
Vince says Romeo and Juliet didn't kill anyone. Actually they did. Romeo killed Juliet's relative then they both killed themselves.
Lumen opens a bag of Peet's Coffee with her new knife. However, that brand of coffee is not sold in Florida.