Former E.R. star Anthony Edwards agreed to return for the medical drama's final episodes, on the condition his paycheck was donated to the African charity he supports.
Although his character Dr. Mark Greene died in 2002, Edwards returns in flashback scenes during the final season of the hit show.
And he is using the opportunity to add raise money for Shoe4Africa, an organisation founded in 1995 that promotes AIDS awareness through sports and education.
He says, "I said, 'Don't pay me. Let's do something different.'"
Producers Warner Bros. agreed to donate the $125,000 (GBP83,000) they had intended to pay Edwards.
In addition to Edwards' money, Steven Spielberg contributed another $125,000 (GBP84,792) and E.R. executive producer John Wells added an extra $50,000 (GBP30,000).
The $300,000 (GBP200,000) total will help build a 250-bed hospital in Africa - the largest children's clinic in the continent.