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TAMPA, Fla. (WFLA) — In the weeklong search for Brian Laundrie, the trail remained cold and silent. There was no sign of him, no breaks in the high-profile case.

At day’s end, it was another frustrating conclusion. Brian was nowhere to be found.

The fiancé of Gabby Petito remains missing, mysteriously vanishing after their cross-country trip, followed by the discovery of her body in Wyoming. It appears the young man has gone off the grid, according to federal investigators. 

It is a daunting, draining task for those assigned to this case. Countless FBI agents all over Florida and across the country are working round the clock, night and day. 

But, if there is someone who doesn’t want to be found, how do you ultimately locate that person? 

Former federal agent Bryanna Fox knows exactly what it takes to take on a case of this size, this magnitude. She’s done it countless times, over and over. 

From the eyes of an agent, she’s been on the inside. Being with the Bureau, she said, is a daily mission where you’re dedicated, determined and deeply focused on a goal. This kind of case where a heartbreaking incident took place, leaving a family without their daughter consumes an agent. 

There was one goal, weighing on your heart and mind, every minute of every day, she said.  

She tells us agents are keenly aware that the family of Gabby Petito is devastated as they endure the aftermath of their daughter’s death. 

Fox said this case has touched lives everywhere for one key reason. Gabby was real. She was relatable.

“It’s a sad case, and people are fascinated due to the fact, when they look at Gabby, they see a sister, a daughter, a granddaughter,” Fox said.

Fox said FBI agents assigned to this case aren’t just working at. They’re living it. The workday never ends, and it never will until the day Brian is found.

A big part of this case, Fox told us, is Brian’s family, specifically his parents and the possible role they played in their son’s sudden and cryptic disappearance.  

 “You can imagine how concerned the parents are about what happened, but they’re also concerned about their son’s future, but at the same time, it is potentially aiding and abetting and helping him to escape,” she told us.

As this case now goes into day seven, it’s a race against the clock for the FBI. Nonstop searching, day and night, all over the country. There is no room for rest as every moment counts, every move agents make must lead to one goal, finding Brian, but it’s not as easy as it looks in the movies, according to Fox. 

“People assume we have access, but that’s not the case,” she said. “What we do is very restrictive. It’s difficult working a fugitive case, as we are doing things to track their messages with other people, financials, every aspect of their lives.”

The key to finding Laundrie, Fox said, is twofold.

His social media is under heavy scrutiny and his inner circle could hold the key to discovering Brian‘s whereabouts. Questioning his family and friends is not enough. FBI agents are digging deeper in the search. It’s not just about his mom and dad, but also acquaintances and others in his inner circle, Fox said, who may be assisting his efforts to hide 

In the end, FBI agents are well aware that this case is more than just a search, more than finding a young man who seemingly wants to remain alone somewhere. 

No contact with the outside world, no contact with social media, and investigator say, no financial transactions. Fox said it’s clear that Brian is elusive and seems to be meticulously careful in concealing his whereabouts as a person of interest. 

“If someone is willing to go off the grid, and live off the land, (it’s) probably the most difficult way to find somebody,”  Fox said. 

Agents want to find the one piece of evidence that cracks the case wide-open, the one that finds Brian Laundrie. FBI agents want to know where he is, and they won’t stop until they find him.

Tips can be called in at 1-800-CALLFBI (225-5324) or online at https://www.fbi.gov/tips.