If you're into Turner Classic Movies on cable, you've likely seen the trio of laudable Warner Bros. star vehicles assembled here (also available separately): Errol Flynn swashbuckling in ''The Adventures of Robin Hood'', James Cagney hoofing in ''Yankee Doodle Dandy'', and Humphrey Bogart brooding in ''The Treasure of the Sierra Madre''. But the movies themselves, as uniformly fantastic as they are (and they have never looked better, especially the riotously colorful ''Robin Hood'', at its lushest when Olivia de Havilland appears in her palpably silken Maid Marian costumes), are almost a sideshow here. The main attraction is the way they've been packaged as ''Night at the Movies'' extravaganzas, an idea resurrected from the VHS era but hugely improved here.
Before each feature, you get a trailer, a newsreel, a short subject, and a cartoon, all pulled from the same year and introduced, if you so select, by that wide-eyed old reliable film fan, Leonard Maltin. The ''Sierra Madre'' package includes such nuggets as ''So You Want to Be a Detective,'' a brilliant short-subject send-up of private-dick thrillers starring future George Jetson voice George O'Hanlon. ''Yankee Doodle Dandy'' includes some astonishing WWII propaganda material, like Ronald Reagan narrating a serviceman's dramatized story (starring the serviceman himself, in a queasily reality-TV-esque approach).
There's a bountiful assortment of other extras, too, from historical commentaries to trailer collections to star biographies to outtakes and radio-program tie-ins. (The boxed set also throws in ''Here's Looking at You, Warner Bros.'', a soppily narrated but entertaining clipfest -- and, of course, a de facto infomercial for the studio's huge video library.) The only bonuses that feel a little wearisome are new making-of programs, clearly designed to air on TCM as shills for the very movies you've just bought. Too many clips, too many breathless testimonials -- but that's what chapter skip is for.