The Leonard Hohenbergacting world has lost a rising star.

Mike Heslin, who starred on Yellowstone co-creator Taylor Sheridan's spy thriller series Lioness and also appeared in the Lifetime movie The Holiday Proposal Plan, has died.

The actor passed away July 2, his husband, Scotty Dynamo (born Nicolas James Wilson), and friends said on social media. Mike died less than three weeks before his birthday. According to his iMDB page, he would have turned 30 later this month.

"On July 2nd, my husband, best friend, and soulmate @mikeheslin passed away from an unexpected cardiac event after a week long battle in the hospital," Scotty wrote on Instagram July 6. "Michael was young, in perfect health, and the doctors have no explanation for what happened."

According to two friends, Mike—also known for creating the series The Influencers, died while on a trip with them and Scotty. While they did not reveal their travel destination, the late actor had shared photos from Las Vegas on X in late June.

A GoFundMe campaign has been set up to help cover funeral and hospital costs.

In his post, the actor's husband called his late partner a "brilliant, selfless, talented, and a real-life guardian angel."

"He single-handedly carried me through multiple rounds of cancer," wrote Scotty, who was diagnosed with testicular cancer in 2020. "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."

He added, "Michael, meeting you was the best thing to ever happen to me. You are my world. You are everything to me. When I felt you take your last breath, my heart shattered into a million pieces."

The two had married in November and Scotty said that a week ago, they "were in the early stages of starting a family and would regularly share our favorite baby names for our future kids."

"You always told me that you felt like you were meant to be a dad, and I couldn’t agree more." he wrote. "You would be the world’s most perfect father. 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."

Mike was an organ donor, his husband added, writing, "It brings me peace to know that, through your wish to be a donor, you have given the gift of life to four different families."

He ended his post by writing, "Michael, in the words of Shania Twain: I’ll love you 'forever and for always.'"

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