Rosie is a 12-week-old puppy described by her owner as a "handful."

Rosie's infectious energy turned into a scary situation Sunday when she eagerly jumped into the car of her owner, John Costello, after a walk near a pond in Canton, Mass.

"The dog jumped in and hit the gear shift and the car jerked … and she fell on top of the gas pedal," Costello told Boston TV station WFXT.

Rosie's move sent the car, with Costello also inside, rolling right into the pond. Costello escaped through the car's front door while trying to rescue Rosie.

"When the car first hit the water I jumped out to grab the dog and she leaped into the backseat," Costello said.

A bystander working nearby heard the commotion and came to Rosie and Costello's rescue.

"I was about 30 feet out from the car," Eric Hermann told WFXT. "The puppy had [been] scared and ran into the back seat."

"The front door was open," he said, noting the two were "trying to get him out of the front door, coaxing him."

As Hermann and Costello worked to rescue Rosie, the car slid further down into the pond and the water level rose even higher.

"I was over my head," Hermann said. "We had to do some swimming."

Rosie's owner, Costello, was still in the water as well and ended up being the one to pull Rosie safely from the car.

"I just leaped in and grabbed the dog and pulled her out, just by her neck and pulled her out," Costello said. "And we both went back into the water."

Police eventually helped remove the car from the water. Costello told WFXT that the car belongs to his daughter and is a total loss.

Neither Rosie nor her two rescuers were injured in the mishap, an incident which Hermann says he has never seen before.

"I work a lot of weekends, none as exciting as this one," Hermann said.