Mark Snow, the Emmy-nominated composer behind the beloved X-Files theme song, has died. He was 78. 

Snow died Friday at his home in Connecticut, a representative confirmed to The Hollywood Reporter.

Sean Callery, a fellow composer and friend of Snow’s, also announced his death on Facebook.

“Mark Snow, and one of the most wonderful and talented people I’ve ever known, has passed away,” he wrote in the Friday post. “33 years ago he began mentoring me as an artist. Who knew that I was also at the beginning of a deep friendship that would only grow and evolve over 3 decades along with our graying hair and tighter deadlines.” 

Callery continued. “I am so grateful to him for his sage counsel and his laugh-out-loud biting wit. My career got started by an act of generosity on his part 33 years ago – period, full stop. I love you my friend. There will never ever be another like you. I send love to Glynnis and all his children and grandchildren during this time.” 

Snow notably composed the iconic opening theme for The X-Files. He worked on the crime drama series during its full time on-air from 1993 until its end in 2018.

Aside from the theme song, he worked on the rest of the show’s music, earning six Emmy nominations throughout his X-Files tenure. Snow, too, served as the composer of the franchise’s 1998 film, The X Files.

A 15-time Emmy-nominated composer, Snow lent his talents to a slew of shows, including Blue Bloods, Smallville, One Tree Hill, Children of the Dust and Ghost Whisperer, among others. His work has also appeared across film, including features in The New Mutants, Ernest Saves Christmas and Crazy in Alabama. 

Snow also frequently worked on TV movies. Some of his past credits include The Boy in the Plastic Bubble, one of his first projects he worked on in 1976 that starred John Travolta, Overboard, Casino, Angel City, Malibu, California Girls, The Lost Capone, An American Story, A Stranger in Town, Trial by Fire, The Perfect Mother, Paradise and Strange Calls.