Molly [as Alexis]: I’m proud of you.
Nathan [as Castle]: Well, remember that when you sing the…[Nathan flubs up his line and swears, then gasps]
Nathan: I mean…I owe you a dollar.
[Off screen] She’s a minor!
Nathan: [quickly] I said I owe her a dollar!
Castle | Season 1 Bloopers
I love this.