Fallon peeked into a doorway thinking Gary had actually walked away, only to discover the hound was coming into the room where he was hosting the show.
“Oh, no, you’re coming in. Gary! You like that? Did you think I called you?” he said while petting the dog, who had a tennis ball in her mouth.
Fallon then was overcome by the pooch’s stench, commenting she needed to get out.
“Kind of a smelly dog. I don’t know what to do with this dog. I really can’t take her right now. Gary, you gotta get out of here. It’s like being in a high school locker room,” he said while tossing the ball out of the room.
“That is something else, man. What is going down?” he added. “I know you’re a dog, but are you, though?”
Gary wasn’t quite finished yet, however, and returned to Fallon, who implored her to leave.
“We’ve had enough,” he said, adding Gary should walk away and take a nap.
Fallon repeatedly told her to “lay down,” causing the animal to sit with the tennis ball in her mouth.
“It’s like she rolled in something insane, dude,” an exasperated Fallon said. “What is happening?”
A few seconds later, Gary sauntered away with a dejected gait.
“I think I insulted her,” Fallon said.
He then promised to give her a treat before pondering the possibility she smelled because of the treats.
“What in the what? That is insanity,” he said.
Fallon is no stranger to having his family become part of his at-home show. Daughters Winnie, 6, and Franny, 5, have often appeared on the program in moments ranging from ignoring him to telling him a secret to informing him about losing a tooth.