| Episode cast overview, first billed only: | |||
| Michael C. Hall | ... | Dexter Morgan | |
| Julie Benz | ... | Rita Bennett | |
| Jennifer Carpenter | ... | Debra Morgan | |
| Erik King | ... | Sgt. James Doakes | |
| C.S. Lee | ... | Vince Masuka | |
| Luna Lauren Velez | ... | Lt. Maria LaGuerta (as Lauren Velez) | |
| David Zayas | ... | Det. Angel Batista | |
| James Remar | ... | Harry Morgan | |
| JoBeth Williams | ... | Gail Brandon | |
| Silas Weir Mitchell | ... | Ken Olson | |
| Salvator Xuereb | ... | John Henry | |
| Jaime Murray | ... | Lila Tournay | |
| Keith Carradine | ... | Special Agent Frank Lundy | |
| Christina Robinson | ... | Astor Bennett | |
| Preston Bailey | ... | Cody Bennett | |
After learning that he was filmed while cleaning his boat at the marina, Dexter becomes desperate and tries to delete the videofile, which he eventually manages to do before computer upgrades enable its viewing by his colleagues. A mock killer mimics, and claims to be inspired by, the Bay Harbor Butcher, and unless the police find him, the FBI may take over the case completely. Following a conversation with Debra, Doakes becomes suspicious that Dexter isn't an addict like he previously thought, and becomes more determined to find out his secret. After learning about his mother's secret relationship with his foster father, Dexter questions Harry's motives about his own adoption. At Rita's mother suggestion, Dexter brings Lila to dinner, and when Rita finds out that Lila accompanied Dexter on his road trip, Rita breaks up with him. Dexter and Lila leave together and have sex later.
Dexter is disturbed with the discovery that his mother and Harry had an affair. When a copycat of the Bay Harbor Killer attacks a former criminal, Agent Lundy promises that the FBI would assume the case if Miami Metro is not able to discover the vigilante. Further, Dexter is informed that there are security cameras in the Coral Cove Marina but the computer system needs an upgrade to watch the footages. Now Dexter needs to find a way to destroy the tape and find the vigilante to avoid the presence of the FBI in the investigation. Meanwhile the poisonous Gail invites Lila and Dexter to have dinner with Rita and her. When Rita discovers that Lila and Dexter had traveled and spent the night together, she breaks up with Dexter and throws him to the arms of Lila. Dexter presents formal charges against Doakes that is stalking him to Lieutenant Maria Laguerta. In the end, the new Dexter fixes all his problems.
"Dex, Lies and Videotape" is another great show of Dexter. Along the story, Dexter is pressed by uncomfortable situations while having an existential crisis, but Lila helps him to resolve the problems and he "makes her understand him" in a very sexy and erotic scene. The insecure Debra finds that Agent Lundy really likes her work. My vote is eight.
Title (Brazil): "Dex, Mentiras e Videotape" ("Dex. Lies and Videotape")