A theatrical decoupage of diverse and autonomous elements, Sasha Waltz’s “Impromptus” ultimately is dominated by issues of besmirchment and purification. The 70-minute piece, which was performed Tuesday night by Ms. Waltz’s Berlin-based company under the aegis of BAM’s Next Wave series, is tedious at times – indeed, it shows how tedium can be an essential ingredient in the theatrical biosphere. But it is never boring.

The stage picture of “Impromptus” engages the audience’s interest before the piece has even begun. The stage is dominated by two playing areas that suggest shifting tectonic plates or a starkly barren promontory. The right platform is steeply raked toward the audience, and much of the piece’s temperament is determined by the challenge of the inclined angle, which instills a built-in tension into the movements. A parallelogram hangs at the back of the stage; it will become kinetic when dancers brush against it and send it shimmying as they exit.

“Impromptus” is performed to Schubert piano pieces and lieder, which were given a distinguished performance Tuesday night by pianist Christina Marton and mezzo-soprano Judith Simonis.The piano and pianist sat on the roofed-over orchestra pit, while the singer intermittently stood on the stage or leaned against the proscenium arch; Ms. Simonis’s mane of red hair set against an alabaster-covered gown certainly contributed to the mise-enscene.But long sections of the piece are performed in silence, which supplies an effective contrast to the music’s strict time delineation.

“Impromptus” begins when a man emerges upstage right, falls to the floor, and slowly rises.Vignettes of resuscitation and regeneration recur throughout the piece. The setting allows Ms. Waltz and her performers to plot formally striking juxtapositions and dichotomies between the two dance areas: A tall and a short woman might be tussling on the left-hand spur while a man crouches alone on the right.

Explorations of weight and counterweight, not emotional effect, are the overriding preoccupation of the duets. People remain autonomous even when they are laced together. They wear stern, trance-like expressions. A man walks over to a woman and they engage in a sort of embrace, but what is more characteristic of the interaction is his subsequent unraveling and rolling her. Central to the dynamic of the duets is reciprocity: One partner visibly leads, then allows himself or herself to follow.

The piece’s primary movement sources include 1960s Judson Church anti-virtuoso dance, which continues to have an enormous influence in contemporary American and European choreography. Jogging and spinning is accompanied by rapid passagework on piano. But much of the work occurs at a snail’s pace, in which the unfolding vocabulary of contact improvisation also becomes a prime determinant. (Co-choreographic credit is extended to the seven dancers.)

“Impromptus” provides a clear demonstration of the way in which postmodern dance renounces the emotional freight of classic modern dance. But the timing of movements, often suggests meaning, and pathological states are as important to “Impromptus” as the deadpan emotional expression. We see a woman shivering, another contracted in fetal withdrawal.The dancers engage in enigmatic rites, suddenly making scraping sounds on the floor as if digging for buried treasure.

About halfway through, “Impromptus” begins to manifest a preoccupation with flowing and splashing liquids when the dancers smear themselves in red paint that goes spilling down the onstage platforms.Two dancers appear wearing waterlogged boots that squeak; later they pour the water out of their boots.A tall woman emerges from what could be interpreted as a primordial morass and begins to rinse sludge off of herself. She is joined by a colleague who also takes her clothes off to rinse away her sins and body paint.

Theatrical sleight-of-hand is at work when we hear splashing and see one dancer’s legs upside down, as if she is submerging into the depths. Following the disappearance of this would-be Rhine-maiden, a final duet occurs in which an apparent somnambulist is stopped in her tracks by her partner, who grips her in a totemic lift. They finally retreat backward away from each other to opposite corners of the rightside platform.

And that is the innocuous end of “Impromptus,” in which tide-pool stillness is revealed as the preface, preocondition, and partner to eventual fecundity.

Until December 10 at the BAM Howard Gilman Opera House (Brooklyn Academy of Music, 718-636-4100).