On with the motley. Hollywood begins to package its feasts, and That's Entertainment! has all the flavour of the Vesta dehydrated line. The wondrous progeny of producers Arthur Freed and - to a lesser extent - Jack Cummings made MGM the home of the film musical. Jack Haley Jr has selected his fave raves, chopped them into skimpy segments, and thrown them together with little rhyme and less reason. Ageing superstars stroll on to recite his deliberately agog script. Little info, no view, no shape, no explanations emerge. The rarity of some items makes a trip worthwhile, but to seek out showings of The Broadway Melody of 1938, Babes in Arms, Meet Me in St Louis, On the Town, The Band Wagon and Gigi would be to learn much more about how Metro and Freed together developed the genre.