In this episode, Veronica helps Cindy "Mac" Mackenzie find and reconnect with her birth parents and siblings. Meanwhile, Keith is temporarily reassigned to the sheriff's department in order to help with a case involving a serial killer.
One morning, Veronica talks to Keith about an old case involving a serial killer, the E-String Strangler, who has made a reappearance. Wallace also complains to her about the panic that's been going throughout the town because of the killer. Sheriff Don Lamb and the mayor of the town meet with Keith. After the conversation, Keith comes out and tells Veronica gleefully that he's going to start working at the sheriff's department temporarily to help solve the E-String Strangler case, but he is getting paid his regular salary. Sheriff Lamb and Keith's conflicting styles immediately become evident.
Meanwhile, Veronica has is being paid by students to dig up "dirt" on their parents' past. As the business takes off, and Mac notices. Mac proposes creating a website for the service and launching it nation-wide, while doubling Veronica's standard fees. Mac casually asks Veronica to look into her parents' past. Veronica finds that Mac's parents once sued Neptune hospital for 1 million dollars. Upon further digging, Veronica finds that Mac was switched at birth with cheerleader (and 09er) Madison Sinclair. Before Veronica broke the news to Mac, Mac's (adoptive) mother walked in the room. Mac's entire family has blonde hair, like Madison, unlike Mac (who has black hair).
Keith and Sheriff Lamb visit a music store to confront the owner about the E-String Strangler's "signature," a type of guitar string. The eccentric shop owner offers little help to Keith and Sheriff Lamb, who then talk to the bartender from the bar which the latest victim was abducted, who leads them to a man called "The Worm" (Aaron Paul). Both of them think "The Worm" is the killer given that he has home-made videos recorded of the murdered girls. "The Worm's" guitar strings also match the strings which were used as the killer's signature. "The Worm" demands a lawyer.
Veronica, Mac, and Wallace invite themselves over and crash Madison's 09er party. Mac looks around the house and meets her biological sister, with whom she connects. Madison kicks Veronica and Mac out of her party, but Mac forgets her purse in the library.
Veronica flirts with a new officer at the Sherrif's department, Leo D'Amato, and steals the Lilly Kane murder files from the evidence room with the help of Weevil. Veronica listens to the tapes she stole, and hears a suspicious synthesized voice. Veronica contacts Mac about the synthesized voice and asks her to help decode the voice.
Mac goes back to Madison's house under the guise of looking for her purse. Madison's mother immediately recognizes Mac as her biological daughter, evidenced by their similar physical appearances. Mac quickly storms out of the house, returning home to her adoptive parents who are about to take Mac on a camping trip. Mac sees her biological mom waiting in the car outside her house, with tears in her eyes. They share a brief connection before Mac leaves to go camping.
Meanwhile, a woman runs screaming into the Sheriff's department reporting a missing daughter who was at a nightclub. Keith breaks into the music store from earlier, citing a hunch. Keith finds a woman locked in a confined box, and is quickly attacked by the murderer: the eccentric shop owner from earlier. Keith is saved by Leo, who was keeping watch for Keith. Later, we learn that the Leo is suspended after Lamb learns someone broke into the evidence room on his watch.
Mac tells Veronica that she's decoded and the message. Veronica eventually says that she knows whose voice it is. The voice is Clarence Wiedman's voice, the man who took unauthorized photos of her. Veronica takes pictures of him and his family and sends them to him at work as revenge.
- Veronica takes advantage of new Deputy Leo D'Amato to steal the Lilly Kane hotline CD and has Mac demodulate the voice, revealing that it was Clarence Weidman who gave the anonymous tip accusing Koonz.
Many cultural references are made in the episode:
- Madison's parents send her a string quartet which plays "Birthday" for her birthday.
- Veronica mentions Rod Serling.
- Sheriff Lamb compares the E-String Strangler case to the Hillside Strangler murders, a real life incident in which two men strangled tens of girls to death.
- Veronica references the Internet Movie Database.
- Keith is surprised that Sheriff Lamb has never seen This is Spinal Tap.
- Mac and Veronica mention Fievel Mousekewitz, a character in the 1986 animated film An American Tail.
- When Mac comes across Lauren Sinclair in the library, Lauren says she is reading The Westing Game. This is a young adult novel by Ellen Raskin, originally published by Dutton in 1978. The plot revolves around a teenage girl who solves a complicated murder mystery involving a large group of possible suspects -- just as Veronica does over the course of the first season.
- Mac derides Madison's art appreciation by saying that she wouldn't recognize Claude Monet's Water Lilies unless Revlon created and named a nail polish after it.
- Keith and Sheriff Lamb decide whether or not to play "Good cop/bad cop" with their suspect.
- Mac's adoptive father references the 2000 memoir A Heartbreaking Work of Staggering Genius.
- The title Silence of the Lamb is a reference to film The Silence of the Lambs starring Anthony Hopkins as Hannibal Lecter.
- When Cindy's mom brings Mac and Veronica some snacks, she remarks that she isn't sure if Veronica was "a normal eater or one of those freakball vegans, like Cindy." Veronica replies that she is "more normal than freakball." Kristen Bell, who plays Veronica Mars, is a vegan in real life.
- Kristen Bell as Veronica Mars
- Percy Daggs III as Wallace Fennel
- Teddy Dunn as Duncan Kane
- Jason Dohring as Logan Echolls
- Francis Capra as Eli "Weevil" Navarro
- Enrico Colantoni as Keith Mars
- Tina Majorino as Cindy "Mac" Mackenzie
- Michael Muhney as Don Lamb
- Max Greenfield as Leo D'Amato
- Aaron Paul as Eddie LaRoche
- Steve Monroe as Gabe
- Christopher B. Duncan as Clarence Wiedman
- Carlie Westerman as Lauren Sinclair
- "Brilliant Sky" - Saybia
- "Fireflies" - Amy Cook
- "The Way You Are" - 46bliss
- This episode was originally supposed to air before "An Echolls Family Christmas".
- Despite being credited, Jason Dohring (Logan Echolls) and Teddy Dunn (Duncan Kane) do not appear in this episode.
- Veronica: Can I get anybody anything? Water? Coffee? [to Lamb] A banana?
- Lamb: Is your daddy here, or is he busy peeking in people's windows?
- Veronica: You stop dressing up like Little Bo Peep, he'll stop peeking.
- Madison: What are you doing here?
- Wallace: I came to celebrate your birth, but these two just wanna hook up.
- Weevil: Well then, you leave the sheriff a note: he shouldn't expect Eli Navarro, Esquire's vote this year!
- Veronica: [voiceover] Same old story. Girl uses boy, girl falls for boy, boy saves girl's dad's life, girl gets what she deserves.
- Jackson Douglas: I hear you do detective stuff for people.
- Veronica: I do favors for friends.
- Jackson Douglas: I can pay.
- Veronica: Sit down, friend.
- Jackson Douglas: I don't care what people say about you, Veronica. You rock!
- Veronica: Yes, I do. I also take cash.
- Keith: [in a guitar store] Hello Cleveland!
- This episode marks the first appearance of Leo D'Amato.
- When Veronica brings Leo the food to give to her dad, Leo's computer monitor shows a "Low Battery Warning" from the Mac OS X operating system. There is no laptop in the scene. Desktop computers don't get low battery warnings.
- When the mother of the newest girl who is missing comes to make the complaint, Leo is the person at the front desk who takes the complaint. In the next scene, Keith interrupts Leo's band's practice to find Veronica. Leo is there, and has no idea that another girl is missing.
- The employee at the music shop's guitar has sound coming out of it, and not the amplifier which must be at least ten feet away.