Note: May have a few spoilers if you didn't watch "Dexter" Season 4 Episode 4 yet.
"Dex Takes A Holiday" is the title of this episode 4, but Dexter takes the very opposite of a holiday--and is in store for a crazier next episode. Rita takes the kids to a wedding for the weekend, leaving Dexter at home for some much needed R&R. However for Dexter having the weekend alone means he does not have to sneak around while targeting his next victim. His victim is a fellow cop, who he accuses of murdering her family--which Dexter reveals to be true. As a cop she, much like Dexter, knows exactly how to stage a murder to make herself look like the victim. The more Dexter learns about this woman, the more Dexter questions his own loyalty and care for his family--in the end he realizes he loves his family and does not want anything bad to happen to them that would destroy it. He finally realizes this in Season 4 Episode 4! I guess Dexter had to go through something like this in order for us to realize his true feelings as a family man.
Meanwhile, LaGuerta and Batista argue over department protocol for exposing a inter-office relationship, which threatens their professional relationship. They both seek advice and safety in Dexter, who helps them both discover what they want from their relationship.
On the case of the 'Trinity Killer' Lundy actually runs into him while both men were scooping out the killers next location. Debra aids in Lundy's investigation and their romantic relationship rekindles; neither of them realizing how close Trinity is to achieving his goals...but you are just going to have to watch episode 4 season 4 to find out what I mean by that. Next episode is going to really expose some blood.