FILM: It's all Marx Brothers all day at the Castro with a double feature of A Night at the Opera, in which they "aid two young singers in love by throwing a production of Il Trovatore into chaos," and Duck Soup, featuring "Groucho lording over the small nation of Freedonia and declaring war on a neighboring country just for the hell of it." (5:30, 7, and 8:45 p.m., Castro Theatre, 429 Castro Street)

COMEDY: Hal Sparks, of Talk Soup, Queer as Folk, and VH1's I Love the... fame, finishes up his weekend at Cobb's tonight, along with guest Myq Kaplan. (8 p.m., Cobb’s Comedy Club, 915 Columbus Avenue)

MUSIC: LA hip hop group, The Philistines, headline Bottom of the Hill, along with Oakland indie rockers, Truxton, and SF-based shoegazy indie quartet, Excuses for Skipping. (8:30 p.m., Bottom of the Hill, 1233 17th Street)