Gary Coleman clashed with Diff'rent Strokes producers because they refused to age his character up

Peacock's revelatory new documentary about the life of Gary Coleman, simply titled Gary, uncovers a clash between the former child star and producers of the sitcom which made him famous — Diff'rent Strokes.

In 1978, Coleman was cast as the precocious, preternaturally charismatic orphan Arnold Jackson on the NBC sitcom when he was only 10, and played the role until the show's final season in 1986, by which time he was 18. His character, however, never seemed to age.

"When Gary was 17," Coleman's long-time friend Dion Mial says in the doc, "he was not comfortable with the fact that the character of Arnold Jackson was aging at the same pace that Gary Coleman was aging."

Due to a regimen of medication used from a young age to treat Coleman's kidney condition, focal segmental glomerulosclerosis, his growth was stalled at around 4 foot 8. This quality made him prime casting for a role like Arnold, but it became an albatross around his neck for the rest of his career.

Diff'rent Strokes casting director Eve Brandstein elaborates that "they didn't wanna change him, you know. 'We have a golden goose.' He was the golden goose, and that caused him pain, emotionally, I'm sure."

Coleman was a virtual unknown before Diff'rent Strokes, having appeared in an unaired pilot of a The Little Rascals reboot, a Medical Center episode, and an (albeit, popular) commercial for a Chicago bank. The anchor of the comedy was Conrad Bain, who'd just come off a seven-year run on Maude. Bain played the wealthy adoptive of father of Coleman's Arnold and Todd Bridges' Willis Jackson. But even before the first season bowed, Coleman had become the series' runaway breakout star.

The Arnold Jackson character and his quicksilver catchphrase, "Whatchu talkin' about, [insert name, usually Willis]" led Coleman to reprise his role in guest spots on series like Hello, Larry and The Facts of Life, in addition to unrelated guest appearances on The Jeffersons and Good Times during his run on Diff'rent Strokes. Coleman was clearly an asset not only to Diff'rent Strokes but the TV networks (ABC picked up the show for its eighth and final season after NBC canceled it in the spring of 1985), who were afraid to tamper with a winning formula.

Diff'rent Strokes hair stylist Joann Stafford-Chaney recalls that Coleman was "just a meal ticket. That's how he felt. 'I'm just making money, but I'm not happy.' He wasn't happy."

Gary pulls from interviews Coleman gave at the time in which he confirmed that sentiment. During a 1985 appearance on The Tonight Show With Johnny Carson, Joan Rivers asks the actor, "Are they maturing you in the show?" He responds. "Not much." When Rivers queries, "Are you complaining?" Coleman plaintively answers, "Of course. Not much I can do about it."

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In the doc, Brandstein notes, "The ratings were declining. I mean, how many times can you deal with the same kind of jokes and the same kind of energy."

The year after Coleman appeared on The Tonight Show, ABC canceled Diff'rent Strokes. "They didn't think that Gary was happy in the character anymore," says Coleman's agent Victor Perillo in Gary. "I think it had run its course."

Coleman struggled to maintain his career post-Diff'rent Strokes. He grew to resent the character, his catchphrase, and the show itself, declaring in 2000, "Diff’rent Strokes must die, and it must die soon... I don't care if it’s a bloody death, I don't care if it's a quiet death, just as long as it dies."

Coleman would continue to make guest appearances as himself on series such as The Simpsons and My Wife and Kids, as well as in films like Dirty Work. He also took on small parts in movies including Church Ball and An American Carol. Later in life, he briefly worked as a security guard and entertained a bid for the governorship of California. In 2010, he died after suffering a brain hemorrhage following a fall he took at his home in Provo, Utah. He was 42.

Gary is currently streaming on Peacock.