Döblin's Berlin, Alexanderplatz is probably a not filmable book anyway. F.e. all the kaleidoscopic elements he has been using like ad slogans, newspaper articles, multiple points of view etc etc etc are really hard to transfer into a movie. Well, it's expressionistic. And definitely outstanding. RW Fassbinder developed a 13-hour-series (plus a rather personal and debatable epilogue) from the material which imho was partly brilliant and partly awfully boring. Of course, the characters had much room to develop here. Whatever, it seems to have gained 'cult' status in some circles. This movie is quite the opposite. It has condensed the original story to a 90-minute-piece which works surprisingly well. Döblin helped with the script, the movie is fast-paced but gets the basic idea of the book. Or better, of it's main character Biberkopf (and also his opponent Reinhold). So, I recommend watching this as at least a comparison to the RWF series. The shots of 1931 Berlin alone make it worthwhile, they add an 'authentic' effect and even Zeitgeist to it (the novel had been published just two years before). That was something the RWF version (shot in 1979) could never really provide.