He has had supporting roles in films such as Stomp the Yard, Down for Life, Jarhead, G, Leprechaun: Back 2 tha Hood, This Christmas, and Miracle at St. Anna. In 2009, he played Fenix "Rise" Calderon, one of the main antagonists in the film Fast & Furious, and had a major role as the Na'vi warrior, Tsu'tey, in James Cameron's science fiction adventure film Avatar. He has made television guest starring appearances on The Unit, Bones, CSI: Miami, NCIS, The Practice and Eyes. Alonso appeared in music videos by Toni Braxton & Aaliyah. Alonso also hosted shows on the BET network.
Alonso was born in Washington, D.C.. He is an alumnus of Howard University. After graduating from Howard University with a BBA in Marketing, he had a lucrative career as an investment banker at Merrill Lynch on Wall Street. He currently resides in Los Angeles.