I've written more than once in this space about the flaws of 'Angels.' It's too long, too sentimental, too inclined to demonize at the expense of comprehension, too rigid in its Marx-flavored politics ('Angels' would be a richer play if Mr. Kushner had had the wit, not to mention the honesty, to portray Ethel Rosenberg as shamelessly guilty). Yet all these things notwithstanding, it remains a fixed star in the firmament of American drama, a testament to Mr. Kushner's willingness to take huge chances instead of playing it safe, and I expect it will continue to hold the stage, both for its genuinely visionary moments and for the character of Cohn, one of the 20th century's great stage villains. Mike Nichols's 2003 TV version was also highly impressive and largely successful, but 'Angels' works best in the theater, and if you've never seen it there, this revival, imperfect though it is, will show you much of what you've been missing.