Javier Guzman is a character in DEXTER. He is a hitman who goes by the alias "El Sapo." He targets Andrew Briggs after Briggs robs a jewelry store owned by Guzman's employers.
In order to get close to Briggs, Guzman poses as a fence. He offers to buy the jewels from Briggs that no one else is willing to buy, since Briggs had stolen them from a store owned by organized crime. However, before Briggs can tell Guzman where the jewels are, he is murdered by Dexter Morgan. Despite this, Debra manages to find the key to Briggs' storage unit where she believes the jewels are hidden.
Guzman begins to follow Debra, believing that she will lead him to the jewels. Debra eventually goes to Briggs' storage unit and finds the jewels. Unfortunately, Guzman shows up, disarms her, and the two engage in a fight. Guzman subdues Debra and brutally kicks her while she is on the floor. He aims a gun at her but doesn't pull the trigger, claiming that he doesn't kill people unless he's paid to do so. Guzman then leaves and takes the jewels out to his car. While his guard is down, Debra approaches and shoots Guzman three times before making off with the jewels.