Over the years, Shannon Keith has written a lot of letters.

Mostly, they don't respond.

Those letters addressed to animal testing facilities, like this one in Nawada, Oklahoma, asking to rescue dogs and cats that would have otherwise been euthanized.

What did you think when you got the phone call from this facility?

I nearly passed out.

This site was in particularly bad shape.

What did you think when you first came here?

I was overwhelmed. There were hundreds and hundreds of dogs living outside in these pens 24/7. When he was doing the testing, the dogs were inside in these dingy, dark, awful, stinky kennels.

But something was different about these 30 acres. And Shannon, who founded Beagle Freedom Project, had an idea for the owner.

We'll buy the property because we want it, and you give us custody of all your animals. And part of that deal was he relinquishes his USDA license so he can never test on again.

These rolling hills are now known as Freedom Fields, a sanctuary while the animals wait forever homes.

We have so much to learn from these animals about love and about forgiveness because they love people so much.

What does it mean that this very same land that was where these animals were being tested on is now their sanctuary?

Yeah, it's hard. It's so bittersweet. Hope they know that they're safe now, and I think they know that and how much we love them.

Savannah Sellers, NBC News, Nawata, Oklahoma.

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