High Quality Content by WIKIPEDIA articles! Melissa Chessington Leo (born September 14, 1960), is an American actress. After appearing on several television shows and films in the late `80s, her breakthrough role came in 1993 as Det. Sgt. Kay Howard on the television series Homicide: Life on the Street for the show`s first five seasons from 1993 – 1997. Having previously been a regular on All My Children and The Young Riders, her breakthrough film role was in the 2003 film, 21 Grams as Marianne Jordan.