There are rules about shouting “Fire!” in a crowded theater. But it’s almost unbearably tempting to yell it during Third Space’s production of “Fireface,” particularly when a Zippo-wielding sociopath begins splashing what is ostensibly gasoline across the narrow stage floor of the Brick, near enough to spray your sandals.

This 1998 play by the German writer Marius von Mayenburg belongs to a deliberately provocative genre that the Germans call “blood and sperm” theater, and that the English describe as “in yer face” theater. Both sobriquets apply here. An explosion of the family romance, “Fireface” observes the incestuous relationship and increasing pyromania of the adolescent siblings Kurt and Olga.

Olga (Rachel Keller) is a lusty teenager with a streak of perversity. Kurt (Tim Creavin), who has a nasty habit of setting fire to dead birds, is rather more troubled. Each encourages antisocial behavior in the other until Olga’s attentions to a motorcycle-riding suitor named Paul (Steven Robertson) thrust Kurt toward even darker deeds. And poor old Mom and Dad (Danielle Delgado and Paul Albe) are oblivious throughout. Until they aren’t.

The script is poised between realism and symbolism, so it sometimes seems the portrait of a distinctly maladjusted family, and sometimes a metaphor for an entire generation resisting the pull of adulthood and the blinkered conformity it demands.

This is a difficult play, but the director, Benjamin Viertel, and his frequently nude cast seem more or less undaunted. Mr. Viertel has a lot of ideas — about lighting, music and performance space — though he sometimes lacks the knack and the budget to execute them convincingly. Many of his choices are inventive and sophisticated; others are unnecessary, and he hasn’t yet managed the trick of getting all the actors to populate the same world. Still, his enthusiasm and ingenuity are very much in evidence, and it will be exciting to see what he and his designers accomplish next.

As long as they don’t burn down the theater first.