Mike Heslin, who appeared in the TV series “Lioness,” died Tuesday, his husband announced.

Heslin’s husband, a recording artist known professionally as Scotty Dynamo, shared news of the actor’s death Friday on Instagram.

In the caption, Dynamo wrote that Heslin died from “an unexpected cardiac event” following a “week long battle in the hospital.”

“Michael was young, in perfect health, and the doctors have no explanation for what happened,” he wrote.

TODAY.com has reached out to representatives for Heslin.

In the caption, Dynamo penned a touching tribute to his husband, whom he married on Nov. 11, 2023, calling the actor “brilliant, selfless, talented and a real-life guardian angel.”

“He single-handedly carried me through multiple rounds of cancer,” Dynamo, who was diagnosed with testicular cancer in 2020, said. “He was the first person everyone would call to share good news with, and he was the perfect person to call if they needed a shoulder to lean on or the best advice.”

Dynamo remembered Heslin as “the sweetest, most caring, and loving man on earth,” and someone who “brought out the absolute best in everyone.”

“Michael, meeting you was the best thing to ever happen to me,” he wrote in part. “When I felt you take your last breath, my heart shattered into a million pieces. If I had the power to trade places with you, I would do it in an instant. But I will take it one day at a time like you always told me to, and live every day in your honor.”

Before Heslin’s death, Dynamo wrote that the couple “were in the early stages of starting a family” and would often discuss their favorite baby names.

“You always told me that you felt like you were meant to be a dad, and I couldn’t agree more. You would be the world’s most perfect father,” Dynamo wrote. “If I ever become a dad, I am going to name my son after you and hope that I manage to raise him to become at least half the man you are.”

Dynamo also shared that Heslin was an organ donor and after his death had “given the gift of life to four different families.”

“We are 3 weeks away from your birthday and 4 months shy of our 1 year wedding anniversary, but I know that you are in a better place and that heaven has gained another angel,” Dynamo concluded the tribute. “Michael, in the words of Shania Twain: I’ll love you ‘forever and for always.’”

Actor Kimiko Glenn, known for “Orange Is the New Black” and “Spider-Man: Into the Spider-Verse,” also shared a tribute for Heslin on Instagram, calling him “my longtime friend, my comfort, my constant.”

“I actually don’t know how to conceptualize my life without you. We’ve drifted alongside each other for 25 years. From doing children’s theater together, to unexpected high school connections, then college, being NY roommates, to moving across the country and catching up on the couch whenever we felt like. Countless memories,” she wrote in her caption.

Heslin was also a director, producer and writer, according to his website. The California native graduated from Boston Conservatory at Berklee and went on to co-found the production house Well-Versed Entertainment. 

As an actor, he made appearances in various shows, including “Younger,” and “I Love You…But I Lied.” In 2020, he created, wrote, directed and starred in the scripted mockumentary series “The Influencers.”

Heslin most recently appeared in two episodes of the Paramount+ series “Special Ops: Lioness” and Lifetime’s “The Holiday Proposal Plan” in 2023.