Laura C. Harris and Daniel Corey in “World Builders” by Forum Theatre (C. Stanley Photography/C. Stanley Photography)

With its pill-dispensing stations and trim, backless sofas, this hospital lounge doesn’t look like a stomping ground for cannibals. But cannibals do lurk here, as do space pirates, lizard people, bio-sculpted human flight machines and an entire cult of demon-worshiping opera singers.

These and other exotic beings swarm through the mind of Whitney (played by Laura C. Harris), a psychiatric patient in Johnna Adams’s idea-freighted play “World Builders.” This intense and confident Forum Theatre production, directed by Amber McGinnis Jackson, takes place in the lounge of a hospital’s psychiatric wing during a clinical trial for a drug to treat schizoid personality disorder. Whitney and another patient, Max (Daniel Corey), have long lived with the disorder, which has left both of them socially maladjusted and obsessed with a personal fantasy universe — in Whitney’s case, a futuristic dystopia populated by 72 alien-human hybrid races, including those cannibals.

But the medication seems to be working, and Whitney and Max recognize that their imaginary worlds may soon disappear. At the same time, as their symptoms lessen, the two develop feelings for one another. Will a romance compensate for the loss of an engrossing fantasy realm? What is it, exactly, that makes life fulfilling and successful? Who gets to decide what’s normal, and why?

Pondering these and other profound questions while mapping the hesitant start of Whitney and Max’s relationship, “World Builders,” which premiered in July at the Contemporary American Theater Festival, in Shepherdstown, W.V., is often more intellectually bracing than emotionally involving. We hear the characters describe their personal fantasy worlds, but for the most part, we don’t share the experience and effect of those worlds, so the prospect of their annihilation always feels theoretical. (By contrast, Adams’s wrenching “Gidion’s Knot” — a two-hander that shares some of this play’s themes — imparts a far more vivid experience of loss and psychologically offbeat subjectivity.)

Still, Harris and Corey deftly expose their characters’ tics and vulnerabilities to considerable poignant effect. The avoidance of eye contact, in the early parts of the play, for example, speaks volumes about the characters’ precarious mental health. Harris excels in twitchy, birdlike movements and other abnormal mannerisms, while Corey’s initially withdrawn demeanor underscores the grimness of Max’s fantasy world, which is as narrow and horrifying as Whitney’s world is exuberant, sprawling and preposterous.

Both characterizations change affectingly during the play, as Whitney and Max get closer to standard-issue sanity. Underscoring that drift toward mental health, small changes take the costumes from psych-ward attire to street clothes. (Debra Kim Sivigny designed the costumes and the set.)

“World Builders” presents an implausibly tidy version of serious mental illness. But you can see why the subject matter intrigued Adams. On some level, Whitney and Max are artists whose creations brim with independence and life. The pair understand the perpetual standoff between unruly inspiration and the rational mind. In short, Whitney and Max are a whole lot like playwrights.

Wren is a freelance writer.

World Builders, by Johnna Adams. Directed by Amber McGinnis Jackson; assistant director, Rebecca Wahls; sound design, Thomas Sowers; lighting, Mary Keegan. About 110 minutes. Tickets: $30-$35. Through Nov. 21. Produced by Forum Theatre at Woolly Mammoth Theatre Company’s Melton Rehearsal Hall, 641 D St. NW. Call 301-588-8279 or visit www.forum-theatre.com.