
This episode covers the double homicide of Chip Northup and Claudia Mppen, the anonymous tip that led to the identification of their killer, Daniel Marsh, and the chilling confessions of a teenage friend, Alvaro Garbe.
Corporal Scott Allen and Corporal Kirath Breznik of the Davis Police Department received an anonymous call on June 15, 2013, regarding the murders. The caller provided detailed information about the crime that had not been made public, leading police to suspect a teenager named Daniel Marsh.
Alvaro Garbe, the anonymous caller, later revealed his close friendship with Daniel and described his disturbing behavior, including a fascination with violence and graphic content. Alvaro recounted how Daniel confessed to him about the murders, detailing the brutal acts he committed.
Despite the shocking confession, Alvaro initially hesitated to report Daniel to the authorities due to fear and uncertainty. Eventually, after a series of alarming events, he contacted the police, providing crucial information that led to Daniel's arrest.
The episode highlights the psychological complexities of Daniel Marsh and the impact of his actions on those around him, particularly Alvaro, who struggled with the weight of his knowledge.
A teenager confesses to a brutal double homicide, revealing chilling details to his friend before being reported to police.

This episode stands out for the following:
I want to tell you something important."Fifteen: A Strange Tip" | "48 Hours" Podcast (Episode 3)
I don't want to hear about it. I want to know about it."Fifteen: A Strange Tip" | "48 Hours" Podcast (Episode 3)
He seemed very content and took a lot of pleasure out of it."Fifteen: A Strange Tip" | "48 Hours" Podcast (Episode 3)
I felt like throwing up, felt like I couldn't feel anything."Fifteen: A Strange Tip" | "48 Hours" Podcast (Episode 3)
You cut both of them open just to see the insides or something."Fifteen: A Strange Tip" | "48 Hours" Podcast (Episode 3)
That's ridiculous. Why is it ridiculous? I'm a kid."Fifteen: A Strange Tip" | "48 Hours" Podcast (Episode 3)