Shazam! star Michael Gray has died, aged 75.

The actor, who was best known for playing teenager Billy Batson in the 1970s CBS television series, died on October 16th, his publicist has confirmed.

His rep revealed to Deadline that Gray died of natural causes.

In Shazam!, Batson would transform into superhero Captain Marvel if he said the word "Shazam!".

The show ran from 1974 to 1976 on CBS's Saturday morning lineup, and Gray portrayed the character for 28 episodes.

Gray previously admitted it was "exhausting" playing Batson, but he also found it "fun" and "thrilling".

Speaking at a Comic-Con panel in 2012, he explained: "I didn't know the character or the story when I was initially cast, so I had to be a quick study - so it was fun and exhausting, challenging and thrilling, all at once.

"It didn't matter that it was on Saturday morning or primetime - though the fact that it was one of the first few live-action shows on Saturday morning was exciting. It truly was a thrilling show to work."

The star also told how it wasn't until "years later" that he noticed what a huge influence his character had on people's lives.

When asked what appealed to him about the part of Billy, he told Fanboy Planet: "I liked it. It was a lot of fun. I didn't know how much I would like it until years later when I found out how much of an influence my character was, and the show was, in people's lives. I had no clue.

"There were such good moral values to the show, and I meet people today, last week, this morning, who say, you have no idea what you did for me as a child.

"You helped me get through life. You made the better man that I am today, or the better woman that I am today. And that's a nice feeling. I didn't know the show had that much strength and power back then."

Gray also starred in NBC's The Little People, alongside Brian Keith and Shelley Fabares, in 1972.

And he appeared as Jeff, the boyfriend of Marcia Brady - played by Maureen McCormick - in a 1973 episode of The Brady Bunch.