As a stroll through the byways of the mind, "Midnight Party" is an unusually engaging configuration of the Walker Art Center's collection. On view for nearly two years, it recently was freshened with new acquisitions and loans and its run extended by six months until August 2014.

The show's inviting title derives from a dreamy little 1938 film by American surrealist Joseph Cornell in which "mystery trumps logic." That also describes the psychological undercurrents in the paintings, photos, installations and sculptures by more than 100 artists spanning 150 years. Their imagery is ripe with the tropes of dreamland -- melting faces and distorted bodies, empty rooms, shadowy spaces, enigmatic gestures and strange things laced with symbolism.

Take the stairway to nowhere. Propped against a white wall, the wooden stairway is a sturdy thing about 5 feet wide with a dozen steps that would reach a mezzanine if there were one. But no, they hit a blank wall and stop, their promise stymied by an impenetrable expanse. A recent acquisition by British-born artist Bharti Kher, the ladder is decorated with swirling, wave-like designs made from tiny sperm-shaped stickers that change from red at the bottom to black at top. Despite the heavy-handed allusions to impotence and futility, the ladder is a potent harbinger of what follows.

As the body is the locus of dreams, it is a recurrent motif. In an unusual Robert Mapplethorpe photo, two beautiful young men dance in a close embrace, their fairy-tale innocence reinforced by princely crowns and trancelike expressions. The female torso, however, becomes a grotesque horror in the hands of Joan Miro, whose "Femme Debout (Standing Woman)" of 1969 is a brazen monster of deformity with thalidomide-flippers instead of arms, boob-like protuberances front and back, and a vulvar slit rendering her torso. Nearby, a covey of mid-20th-century art heroes -- Mark Rothko, Jean (Hans) Arp, Willem de Kooning, et al. -- let loose their bad dreams in abstractions full of bosomy bumps, harridan screams and grumpy colors that beg for psychoanalysis.

A strange fiberglass "Snowman" sculpture by Bonnie Collura continues the theme in the next gallery, its white body slumping into a mass of misshapen body parts. German artist Thomas Schute amplifies the motif in two photos of grotesque, beady-eyed faces sculpted from plasticine, and a bell jar holding three doll-sized figures in liturgical robes, bound together as if for an inquisition. Nearby hangs Francis Bacon's "Head in Grey," his 1955 painting of a Ronald Reagan look-alike whose face is smeared, as if streaked by acid or acrimony.

Soulful rooms

That existential vacuum that sometimes grips the somnambulant soul finds expression around the corner in Robert Gober's 1987-88 installation consisting of a creamy ivory door frame inset into a gray wall. The opening leads into a small, bare, brightly lit white room in which a door leans against a wall. Displaced from its frame, the unhinged door is helpless to protect the room's inhabitant from scrutiny, interrogation or whatever anxieties or pleasures a racing mind might imagine.

Two more rooms call out from the welter of strange and wonderful things in "Midnight Party": an installation by Kiki Smith and a little gallery of paintings by Marsden Hartley, one of the 20th century's most tormented artists. Smith's room, which you enter through a jagged tear in a wall, is a dollhouse of the psyche, a kitchen-like space in which a child-sized sculpture of a girl is surrounded by colonial-era crockery, stenciled wallpaper and chalk drawings of women in old-fashioned garb. Reaching for the sky, the child apparently yearns for a future she can't yet read (note the current newspaper that's placed in the installation each day). As in too much of Smith's work, didacticism threatens to overwhelm poetry. Still, the little room works its magic.

The nine Hartley paintings are all still-lifes, heavily laden with personality. Five are on loan from the University of Minnesota's Weisman Art Museum. Most are gifts to the museums from descendants of the Walker's founder and namesake, T.B. Walker, a man of conventional taste who doubtless would have disliked both the pictures and the closeted gay man who painted them.

Hartley's paintings are a perfect aperçu given the sexual motifs, body issues and psychological dramas that permeate "Midnight." Most famous for his symbolic portraits of a World War I German officer with whom he was in love, Hartley imbued every brush stroke with raw energy, sexual tension or bleak despair. Even the folkloric carvings in his "Santos, New Mexico" are tersely ambiguous, including a king in a pink-bowed dress holding a baby while a paw-like human hand hovers above him like the appendage of a malign god. And it's impossible not to see Hartley's own haunted, hangdog features in the three hollow-eyed faces that dominate his "Masks" of 1931-32.

Analysts doubtless have plenty of theories to explain molten bodies, bizarre encounters and the claustrophobic interiors we encounter in the landscape of dreams. Such theories go a long way toward explaining life, yet when it comes to art, these denizens of midnight party on. • 612-673-4431