Dexter uses the line "Tonight's the night" in one of his monologues. This line was also used in the pilot episode.
(Dexter sprays luminol around to look for blood in the warehouse where Lumen shot her victim)
Lumen: What are you doing?
Dexter: It's Luminol.
Dexter: No relation.
Dexter: You killed somebody.
Lumen: Because you wouldn't do it for me!
Dexter: But you call me to clean up after you.
Lumen: I didn't know what to do with the body!
Batista: Stay single as long as you can.
Deb: Says the newlywed.
Batista: Don't remind me.
Deb: You've been married for five minutes. What happened to the honeymoon phase?
Batista: I blinked.
Dexter: (voice over) Compartmentalization began as an architectural theory, divide buildings into sections which can be closed off to prevent a fire from spreading. Life can also be divided into closed-off sections. Makes everything much simpler.
Dexter: (voice over) I've always tried to keep the different parts of my life separate. Becoming a father made that much more difficult. And as a husband, I failed. But I'm a very neat monster who won't make the same mistake again.
Although credited James Remar (Harry Morgan) does not appear in this episode.