Maggie’s grandmother runs an animal clinic, Dr. Mac’s Place, so Maggie knows her way around animals who are in danger. When she learns that the abused and sick puppies flooding the clinic are from an illegal puppy mill, she knows that she has to find out who’s running it, where it is—and save the rest of the dogs!

Brenna, Maggie, and Zoe go to Florida to visit a manatee rescue center, where they learn about these endangered marine mammals.

Seeing Jane's dog, Yum-Yum, help cheer up children in a cancer ward makes Zoe think about having her puppy, Sneakers, trained to do therapy, too, especially when Yum-Yum becomes very ill.

Adjusting to middle school becomes easier for twelve-year-old Maggie when she finds that her biology teacher, who is blind, can learn a few things from her about working with his guide dog.

After assisting with her own cat's emergency surgery, Sunita decides she can no longer work with animals and accepts an internship at a lab, unaware that the research conducted there includes animal testing.

Sunita and her fellow volunteers at the Wild at Heart veterinary clinic become involved in efforts to save a bunch of feral and abandoned cats with the help of Dr. Mac.

Zoe is unhappy about leaving Hollywood to live with her cousin, Maggie, and grandmother, Dr. Mac, in Ambler, Pennsylvania, while her mother is away on a film shoot, but soon gets involved in a suspected case of antifreeze poisoning.

"Meet Jules and Josh, the new twins in town! While Josh adapts quickly to Ambler, Jules accidentally makes an enemy of Maggie. Hoping a pet will help her feel better, Jules adopts the class rabbit, Chewie, but things go downhill when there are complications with Chewie's spay surgery. With Dr. Mac out on a call, it's up to Jules to work with Maggie to help the rabbit - and maybe even prove that she and Josh are worthy of becoming Vet Volunteers."--...

When they find abandoned ducklings, the vet volunteers must educate the community about keeping baby animals as Easter pets while also teaching the ducklings how to swim.