"Andy Warhol: The Last Decade" at the Brooklyn Museum is an utterly fascinating show. For one thing, the contents of the exhibition mirror the identity of the new, improved Brooklyn Museum: when they are good, they are very, very good and when they are bad, they are hideous.

Start with the last room in the exhibition. Here you have the best of "The Last Suppers," the austere and solemnly grand yellow one cattycornered with 112 Jesuses, a lame series of neon signs from the Bible Belt. A searing orange self-portrait in which Warhol's head drops like a stone is contrasted with a purply pink-and-black self-portrait which horribly puts Warhol's head through the spin cycle.

In many ways, interpreting the "Last Decade" is hampered by the backward kaleidoscope of the ridiculous and ghastly circumstances of Warhol's death at the hands of a hospital: our feelings that he must have foreseen it in this work are merely a pathetic fallacy. If anything, under the mercantile guidance of Fred Hughes and Vincent Fremont, Warhol was throwing any idea against the wall in order to Velcro the dollars.

Andy's biggest mistake was diving headlong into the poisoned well of kitsch, where cheeky irony had once served him so well. The doodling knockoffs of Jackson Pollock done in electrical cord style and the Rorschach tests that echo Jean Dubuffet are nothing more than bad decoration. He desecrated the majesty of his own "Marilyns" by dipping them in a murky pool of necrophilia and minstrelsy. Only a trust-funded cocaine addict could love this junk.

The large collaborations with Jean-Michel Basquiat, which the Brookyn wisely included because they are so unfamiliar, have their moments, but fail, in the end, because Basquiat is obviously holding back his best pictorial efforts for his own work. Then there are the silkscreened devotional Jesus and grocery price-tag images, stupidly combining what Warhol liked to fake were his two main preoccupations, Catholicism and dollars (rather than making great art and chasing boys). No amount of rationalization can save this garbage from the dumpster.

And yet, and yet. . . Andy still produced two of his most enduring series in the "Last Decade," the "Shadows," which must be seen in one huge room at Dia Beacon and the "Camouflage Series" (both abstract and abstracted self-portraits). It is instructive, perhaps, to think of the two bodies of work as intertwined, a kind of Warhol water lilies, a bit of Monet, because what the "Shadows" and the "Camouflages" do is to free color from light. The range of colors with a zone of repetition in the two series is so overwhelming as to shoot the shades right through the eye into the brain and, not to make too fine a point of it, solve Duchamp's problem of retinal art. Trust Warhol to produce his greatest work even when he was fucking around with throwaway kitsch.

"Andy Warhol: The Last Decade," June 18-Sept. 12, 2010, at the Brooklyn Museum, 200 Eastern Parkway, Brooklyn, N.Y. 11238

CHARLIE FINCH is co-author of Most Art Sucks: Five Years of Coagula (Smart Art Press).