UFC 21: Return of the Champions was a mixed martial arts event held by the Ultimate Fighting Championship on July 16, 1999 at the Five Seasons Events Center in Cedar Rapids, Iowa. The event was seen live on pay per view in the United States, and later released on home video.
| Actor | Role |
|---|---|
 Maurice SmithSelf | Self |
 Marco RuasSelf | Self |
 Pat MiletichSelf | Self |
| AAndre PederneirasSelf | Self |
 Jeremy HornSelf | Self |
 Daiju TakaseSelf | Self |
| PPaul JonesSelf | Self |
| FFlavio Luiz MouraSelf | Self |
| TTsuyoshi KohsakaSelf | Self |
 Tim LajcikSelf | Self |
 Royce AlgerSelf | Self |
| EEugene JacksonSelf | Self |
| AAndre RobertsSelf | Self |
| RRon WatermanSelf | Self |
 Travis FultonSelf | Self |
| DDavid DoddSelf | Self |