They found them dead on the back of the pick-up they had left to celebrate their first anniversary. Then, about 30 meters from the bodies, the investigators found a camera destroyed.
When they were able to develop part of the roller, Lisa and Brandon were still alive.
It was October 17, 2003.
Lisa Gurrieri was 19 years old, Brandon Rumbaugh 20. They lived in Scottsdale, Arizona, and they were together for a year.
To celebrate that anniversary they had decided to spend a night camping in an isolated area north of Phoenix.
They borrowed from Lisa's mother a white Ford F-150 and brought with them Lisa's mother's camcorder.
During the journey they made a purchase that, at that time, had nothing special: a disposable camera.
They just wanted to keep some memories that night.
Lisa's mother talked to them while they were still on the road. Everything seemed normal. The program predicted that the two boys came back the next morning.
But Brandon didn't show up at work.
Lisa didn't come home.
When family and friends realized something was wrong, they started looking for them.
On Sunday the pick-up was located in a secluded area near Bumble Bee Road.
Lisa and Brandon died in the back of the vehicle.
According to the investigators, they were attacked at night, maybe while they were sleeping or getting ready to sleep.
Some objects were missing from the scene.
The camera they borrowed had disappeared.
Lisa's keys weren't even found.
Then, about thirty meters from the vehicle, the disposable camera was recovered.
It was damaged.
The roller, however, was not completely lost.
The investigators were able to retrieve some photographs.
In one you see Lisa sitting on the pick-up bin.
In another, Brandon appears at the same point.
Around them there is only the darkness of the night.
They are considered the last known photographs of the two boys still alive.
And that's what makes them so difficult to look at, knowing what happened later.
Lisa and Brandon just seem like two guys who are spending a night together. Nothing in the pictures, according to investigators, suggests they knew they were in danger.
But there was another photograph on the roller.
And that's what, in the following years, would have fed numerous theories on the internet.
The image is almost entirely overexposed. The light has erased much of what was photographed, leaving only a small portion visible.
In that fragment it seems to be able to distinguish a lamp and part of the interior of an environment.
From there were interpretations of all kinds.
There are those who believed to see the inside of a camper, who a basement, who a car and who an unknown room connected somehow to the murders.
For years, that photograph seemed to contain a possible mystery in the mystery.
But the investigators gave a much less disturbing explanation.
In 2023, Tom Boelts, commander of Yavapai County Sheriff's Office, explained that photography could have been accidentally taken while someone threw away the camera.
The small recognizable part would also appear to show the inside of a Bumble Bee club that in 2003 worked as a restaurant.
This could mean that the most discussed photograph of the roller has no direct connection to the identity of those who killed Lisa and Brandon.
But there remains a much more important question.
Who killed them?
Over 20 years, no one was arrested for the two murders.
Investigators continued to re-examine the evidence and work on DNA recovered on the scene, using genetic genealogy in the hope that new techniques could provide a track that in 2003 would be impossible to get.
There are still people of interest, but the case has not had a definitive solution.
And so that little disposable camera remains one of the most significant objects of the story.
Not because it necessarily contains the photograph of the killer or the answer to the mystery.
But because it keeps something that no investigation can rebuild.
Lisa was 19. Brandon 20.
That night they didn't know that the photographs they were taking to remember their first anniversary would become the last known pictures of them alive.
They started thinking about coming home the next morning.
More than 20 years later, someone is still trying to figure out who prevented them from doing this.