The Earl Carroll Theater, named after and operated by the eponymous Broadway showman of the twenties and thirties, opened on Sunset Blvd. between Vine and Gower in 1938. In 1954 it became the Moulin Rouge and in 1965 it became the Hullaballo, a club exclusively geared toward the burgeoning rock and roll youth market. No alcohol was sold, the bands that played there were either on their way up (Neil Diamond, The Doors in 1966) or already up (The Turtles, The Byrds, Nitty Gritty Dirt Band) and the ‘kids’ were strictly in the transition era from clean-cut to long hair, with psychedelia threatening on the periphery. Above is a short newsreel (I don’t know what else to call it and I’m not sure why it was even produced) about the opening of the club and explaining and sort-of promoting the place. Here’s an excellent website with a page devoted to history and photos of the theater. By the way, the location of the building is not on the Sunset Strip, as is mistakenly labeled. It’s on a much less glammy (even then) chunk of the street in deeper, darker Hollywood.