Mark Alexander Knox (born April 15, 1970), better known as Flex Alexander or Flex, is an American actor, comedian and dancer.
Born in Harlem, Alexander is the son of Alethia Knox and Robert Whitehead. As a teen, he began dancing in New York clubs earning the nickname “Flex” due to his acrobatic dance skills. After being discovered by DJ Spinderella, he began touring with rap trio Salt-n-Pepa’s dance troupe for three years. In addition to dancing, Alexander also choreographed for Mary J. Blige and Queen Latifah. In 1989, he made his stand-up comedy debut and eventually turned to acting, making his film debut in the 1992 film Juice. Alexander also was a regular cast member of the sketch comedy show, Uptown Comedy Club, from 1992-1994.
Alexander’s first television role was on the short-lived 1993 ABC sitcom Where I Live, starring Doug E. Doug. Despite being critically acclaimed, the series was cancelled that same year. Alexander then guest starred on episodes of Sister, Sister and The Cosby Mysteries before moving to Los Angeles in 1995 to concentrate on acting. In 1996, he landed a starring role on another short-lived sitcom Homeboys in Outer Space. The series was critically panned and cancelled the following year. Later that year, Alexander co-starred in yet another short-lived series, the Steven Bochco-created Total Security. Following Total Security’s run, Alexander guest starred on Brooklyn South and The Parkers, and also had roles in several films including the 1998 direct-to-video release Backroom Bodega Boyz and She’s All That (1999).