That this film shared the 1980 Palme D'Or with Kurosawa's Kagemusha makes it sound pretty good. Unfortunately the latter film was a ponderous affair and indeed, it is hard to tell which is the more punishing viewing experience.
Essentially it's a re-working of the time-honoured let's-put-on-show musical with Roy Schieder as the (non-dancing) Gene Kelly-type dancer-choreographer, Joe Gideon The fact that Fosse based it on his own life does not manage to lift it beyond the often wincingly clichéd, both in terms of plot and direction. Whilst this might have looked pretty cool in its day, as the opening number, a cattle-call to George Benson's On Broadway that looks like an outtake from Fame (1980), with wall-to-wall leotards and leg-warmers indicates, it has dated badly, both visually and musically.
However, if you can wait that long, the final number, which has Gideon dying to The Everly Brothers' 'Bye Bye Love' is a marvellous piece of black humour and bad taste (continued over the credits with Ethel Merman's version of 'There's No Business Like Show Business'). Despite the prominence of her name in latter day publicity Jessica Lange, then still languishing after her turn in King Kong (1976), has a literally lightweight part as an angel.