Mark Alexander Knox (born April 15, 1970), known professionally as Flex Alexander or Flex, is an American actor, comedian and dancer. Having made his television debut as Reggie Coltrane in the critically acclaimed ABC sitcom Where I Live (1993), he became known for his role as single father Flex Washington in the UPN sitcom One on One (2001–2006), for which he was nominated for three NAACP Image Awards. Alexander was nominated for a fourth NAACP Image Award in 2005 for his portrayal of Michael Jackson in the VH1 biographical drama Man in the Mirror: The Michael Jackson Story. He has also appeared in films such as Juice (1992), She's All That (1999), Snakes on a Plane (2006), and The Hills Have Eyes 2 (2007). Alexander has had recurring television roles in the UPN sitcom Girlfriends (2000–2001), the VH1 comedy-drama series Single Ladies (2012) and the ABC sitcom Mixed-ish (2020–2021). (Via Wikipedia)