May the ghost of Gertrude Vanderbilt Whitney forgive me, but I really miss Caligula. That is, I wish that the thoughtful but tepid current edition of that impossible curatorial predicament known as the Whitney Biennial contained at least one pulse-quickening phenomenon like Francesco Vezzoli’s faux-porn Trailer for a Remake of Gore Vidal’s ‘Caligula’ in the 2006 show. (I dismissed it back then as merely filling “the arty cineplex slot.” Ah, but what’s life without regret?)

In 1948, at the age of 20, Yves Klein laid claim to the kingdom of the sky.1 Its presence hovers in the monochrome blue panels he began painting in 1955. But Klein’s blue is not the pallid tint of the daytime sky. It is the dark, electric blue of the Paris sky at nine o’clock on a summer night, when the energy of the vanished day still resonates through the atmosphere, and the headlights of the traffic seem like sparks descending from above.

Robert Morris has re-created one of the key works of Post-Minimalism, Untitled (Scatter Piece), 1968-69, at Leo Castelli Gallery on 77th Street. First exhibited along with Continuous Project Altered Daily at the Castelli Warehouse on West 108th Street in March 1969, Untitled (Scatter Piece) traveled to the Corcoran Gallery of Art in Washington, D.C., the following November as part of an early Morris retrospective, but was not sent to the exhibition’s next venue, the Detroit Institute of Arts. Instead, it was returned to storage, and subsequently disappeared—curious, since it consisted of 100 hefty pieces of metal and 100 pieces of heavy-duty felt, and weighed about 2 tons.

A Japanese modernist’s retrospective reflects a deepening respect for the art and ideas of Gutai.

Epic in scope, enigmatic in content, 120 paintings by Rauch are on view in a dual-venue 10-year retrospective, the largest survey to date of the Leipzig-based art world superstar in his native Germany.