The Manica Lunga, or “long sleeve,” of the Castello di Rivoli takes its name from its shape. It is a long, relatively narrow wing of the building—a corridor studded with windows. Although the exhibition space is usually difficult to handle, it might nonetheless be almost perfect for John McCracken’s sculptures. Brightly colored and almost sparklingly vivid, positioned in the space with great freedom, they make the Manica Lunga look as if it were inhabited by creatures from another dimension, similar to the cosmic realm of the aliens to which the artist alludes in his work and which he