Delia D'Ambra

There were no obvious signs of trauma.

However, the Sheriff's Office later walked back that statement when a spokeswoman for the agency clarified that there were signs of physical trauma initially observed on the victims.

But as far as what those traumatic injuries were, the Sheriff's Office didn't immediately clarify.

The following day, Monday, October 20th, the Yavapai County Medical Examiner's Office concluded Brandon and Lisa's autopsies.

And the day after that, authorities announced at a news conference that both victims had died from multiple gunshot wounds to the head, apparently inflicted while they'd been asleep.

Neither of them had drugs or alcohol in their system, and there were no indications that a robbery or sexual assault had taken place.

So from the start of the investigation, the sheriff's office had very few leads to follow.

They knew they were dealing with a double homicide that had taken place sometime Friday night or Saturday morning.

But other than that, clues pointing to a particular suspect or suspects were slim.

For example, investigators hadn't found any shell casings or tire tracks at the crime scene, and initial observations also ruled out a murder-suicide situation.

Now, despite a seeming lack of physical evidence, what authorities did have was a fairly detailed timeline of the couple's last movements and communications.

When they'd left to go camping on Friday evening, Brandon and Lisa told their friends and family members that the plan was to borrow Paula's truck and drive about an hour north of Phoenix to go camping off Interstate 17.

During their drive, Lisa had spoken with her mom because Paula had called to check in and see how things were going.

During that conversation, Paula said everything seemed normal, and Lisa explained that she and Brandon were still on their way to the spot they wanted to go camping.

The geographic location they'd set their sights on was an area known as Bumblebee, and it's actually where the couple had gone on their first date one year earlier.

Their original plan for celebrating their one-year dating anniversary was to go to Disneyland, but the price tag for that excursion ended up being more than they wanted to pay.

So they'd settled for doing something more low-key and sentimental.

Lisa's mother, Paula, told reporter Emily Bittner that the pair was looking forward to parking her pickup truck off Bumblebee Road and spending time together outdoors and stargazing before eventually drifting off to sleep.

Lisa had told her mom that her and Brandon would return Paula's pickup by Saturday morning because Brandon was actually scheduled to work as a personal trainer at a gym in the nearby city of Mesa that day.

When Lisa and Brandon were overdue on Saturday, Paula thought it was strange because she knew her daughter well enough to know that Lisa would have called if her and Brandon were running late.