When Prince's dazzling and dynamic Purple Rain (movie and soundtrack album) and the hypnotic hit single "When Doves Cry" exploded onto the pop-culture scene in 1984, it seemed there was nothing the purple one couldn't do. The film is basically a feature-length music video, but no musician has ever had a better big-screen showcase for his many talents. The plot is really just a theme (about the son of an abusive father struggling not to continue the pattern) upon which to hang some of Prince's most dazzling songs (including "Let's Go Crazy" and the title tune), and some sizzling live- concert numbers. Apollonia Kotero is ravishing as the romantic interest, and Morris Day and the Time provide some terrific musical competition. Purple Rain is an essential artifact of the mid-'80s pop Zeitgeist. Prince took home an Oscar for the song score.