By Cara D. Clark

It’s likely you’ve heard Adam McArthur voiceover work on Cartoon Network, Disney, Netflix and many more of your favorites channels. But he’s more than just a familiar, friendly voice, he’s gained acclaim as an entrepreneur with an innovative Photo Booth idea, The Booth & Bus Co. Though he’s surely well-known as an actor and improvisor, his biggest fan doesn’t know him for his screen credits. River Cooper, a bright-minded terrier mix, knows him as the dad with the great ideas and yummy treats.

It’s a mutual admiration society between these two. That’s clear when Adam’s first comments are about the canine’s beautiful eyelashes, just one of ways the 1-year-old terrier mix rescue tugs on McArthur’s heartstrings.

River was named for his wife’s favorite tradition of taking a family river trip since she was teenager, “a reminder of something she always loved,” McArthur said. It was his wife who brought the pup into their home a year and a half after the family lost Cooper, McArthur’s first-ever dog and constant companion. Cooper, an 18-pound terrier mix that looked mostly Yorkie, was rescued at 2 years old and quickly found a permanent place in the heart of a man known among fans for voicing four-seasons as Marco Diaz on the hit Disney XD series Star vs. the Forces of Evil.

“Cooper was irreplaceable, but I’ve learned you can still love another dog,” McArthur said. “I never had pets growing up — I had a turtle at one point, and my grandparents always had dogs. When I graduated from college, I was living in Los Angeles and wanted a little buddy to take on walks. I got Cooper, and he was my best buddy. He was amazing.” When Cooper died at 14, McArthur’s grief was difficult to bear.

“I thought, why would anyone be willing to go through something like that more than once,” he sad. “My wife was adamant about wanting a dog so she took the lead. I said, ‘You go for it.’” His wife did just that and began messaging The Label Foundation, a no-kill shelter in Los Angeles. It took some time but she discovered River after the pup was transferred from a kill shelter in Bakersfield, Calif.

“It was the right time for us and for River - she is truly a blessing,” McArthur said. “She’s amazing — so sweet, very energetic, cuddly and loving, affectionate, everything you could want in a dog and more.” The perky pooch had siblings on the same truck, and the McArthurs have kept in touch with the other owners and River’s kin via Instagram — two of her brothers, Puff and Leo, have even had playdates, a veritable Barkfest, in the McArthur’s backyard.

River is quick to pick up on tricks and easily caught on to sit, lay down, shake, fetch, and high-five. She also does a sweet face-to-face “boop” where she bumps noses with her human dad, and she’s working on hugs. Her most recent trick is a showstopper in McArthur’s which was built circa 1926 with a vintage mail drop in the wall. He taught River to go into the cubby hole, grab the mail and bring it to him.

“She is so cool,” said the veteran of comedy fests including San Diego Comic Con and Stan Lee Comic Con. “I tell her to go get the mail, and she does it. It’s awesome.” What’s her reward? Kisses and treats. What more could a pooch want?

McArthur says the secret to the trick’s success is noticing River’s interest in the sound of the mail drop and her natural curiosity to see what was going on. “That was the key with her,” he explained. “We would hear the mailman, and I would say, ‘Go get the mail.’ Noticing what she did naturally and using receptive commands works. It’s fun to work with her. I know her so well that I can tell by the look on her face what she’s thinking. She’s such a clear communicator.”

While McArthur might be River’s biggest fan, he has a loyal following in the voiceover community on all social media platforms with more than 40,000 Instagram followers and 36,000 Twitter followers. When asked if he ever uses his voice skills to entertain River with different characters, he pauses thoughtfully. He says that’s something he hasn’t considered. It’s possible he’ll add that to the rotation of their interactions. With her bright mind and eagerness to please, she’s sure to catch on quickly and enjoy the game.

Catch up with McArthur, whose voice can be heard as the lead in the hit anime series Jujutsu Kaisen, which is based on the popular Japanese manga series of the same name. The show is streaming now on HBO Max and Crunchyroll.