Malissa Sergent Lewis wasn't expecting to save a life on her way into the office last week. But that's exactly what she did.

Malissa Sergent Lewis

On Thursday morning, Lewis was running a little late to the elementary school in Kentucky where she works, so she decided to take a shortcut through a back road instead. It was there along that quiet country street that, despite her hurry, Lewis took notice of something shockingly out of the ordinary.

"I saw this trash bag in the road, and I thought to myself, 'Did I just see that bag move?' The closer I got, I realized it was moving," she told The Dodo. "I could hardly wrap my mind around that. Something was alive in that bag, and I just knew I had to get whatever it was out."

Video Lewis captured on her cell phone shows the trapped creature hobbling toward her approaching vehicle.

Not knowing if it was a dangerous sort of animal inside the bag, Lewis approached with caution. But she helped regardless.

"The bag was tied off in a knot, so I carefully tore a corner and looked inside," she said. "It was a puppy. And he sure was glad to see me. As soon as I opened it up, and he saw light, he just started wagging his tail. He knew he was OK. I couldn't believe it."

Malissa Sergent Lewis

The puppy was wearing a collar, but had no tag to identify where he came from β€” so Lewis decided to take him with her. (After all, she was still late for work.)

"I just put him in my lap and drove to school," she said. "I couldn't just leave him in the car, so I brought him in with me. The principal saw me and said, 'You have a dog!' I said, 'It's a long story.'"

Lewis called her son to come pick the puppy up and take him to the safety of their home. Later on, they took him to the vet to make sure he was truly all right after that unimaginable act of cruelty.

"We got him his shots," she said. "He seems happy and healthy."

Malissa Sergent Lewis

It isn't known if the puppy had been discarded by his owner, or was perhaps stolen and put there by someone else. Lewis says authorities are investigating the case, but there's no doubt in her mind someone did it on purpose β€” and that he would have likely died had she not been fortunate enough to spot him in time.

"Who could do something like that to any animal? I don't care who you are; everybody loves puppies," she said. "It's a real coldhearted person to put an animal, any animal, in a garbage bag and dump it on the side of the road. They had bad, bad intentions doing that."

Thankfully, though, the puppy found just the person to help him, not just in that desperate moment, but for a lifetime.

Malissa Sergent Lewis

It's only been a few days now, but Lewis and her family have already bonded with the little dog she saved. They've even given him a name hinting to the circumstances of his chance discovery: Hefty.

Things for him are now looking up.

Malissa Sergent Lewis

Since there's a good chance no one will ever come forward to claim Hefty, Lewis and her family have decided to give him a forever home themselves.

"We all love the puppy," Lewis said. "He's going to be loved, and have a good home with us. I'm just glad I was in the right place at the right time to save him. That's what it was."