New surveillance video has surfaced of Gabby Petito with Brian Laundrie days before her death.

The video shows the couple parking and shopping inside a Whole Foods in Jackson, Wyoming, on Aug. 27. 2021.

Dr. Joe O'Connor, a communication specialist and a body language expert, says the surveillance video is telling.

"He's always walking behind her like they're almost purposeless - they're kind of just floating around," O'Connor says. "When was the last time you went into a grocery store and you didn't get food? That's telling."

Just before they were at the grocery store, Petito and Laundrie were at a nearby restaurant where witnesses saw Laundrie having a public argument with the restaurant's employees and also stormed in and out of the restaurant four times before Petito apologized to the staff.

O'Connor says Laundrie has his hands in his pockets to suggest he is guarded and to himself, and Petito's body language shows her arms crossed to suggest being scared.

"They actually hug themselves - they're so defensive and so afraid and so uncomfortable," O' Connor says.

The video shows them looking at products in different sections of the store, and at one point Petito is alone.

The Blue Point native was reported missing on Sept. 11.

Petito's body was found days later at Grand Teton National Park.

Laundrie, who was later found dead of a self-inflicted gunshot wound, was the only one identified by law enforcement as a person of interest in the case.