Playwright Lucy Prebble attempts to cover an expansive range of themes in the North American premiere of her play “The Effect” at the Barrow Street Theatre. Although this choice gives her play a range of diverse and interesting conflicts, it fails to give the play a cohesive core leaving the audience to wonder what Ms. Prebble was trying to accomplish. Is “The Effect” about the over-prescribing of psychotropic medications? Is the play about the irresponsible behavior of clinical trial participants Connie Hall (Susannah Flood) and Tristan Frey (Carter Hudson) and by extension all Millennials? Or perhaps the play is about regret and revenge.

When Connie and Tristan enter the clinical trials for a new anti-depressant medication, they pledge to the study’s supervisor Dr. Lorna James (Kati Brazda) not to use cell phones (they interfere with the clinical equipment), not to engage in any sexual activity (Connie is the only female participant and Dr. James assumes they are both straight), and to keep their monitoring devices on at all times. The pair manages to break all the rules and assume their heightened interest in one another is the direct result of the increasing doses of the trial medication. So “The Effect” might be about what causes people to be attracted to one another – especially if they are straight.

Under David Cromer’s careful direction, the ensemble cast members deliver spirited performances and maneuver skillfully through the playwright’s plot surprises and thematic strands. Of particular interest is the parallel between the relationship between Connie and Tristan and the relationship between Dr. James and Dr. Toby Sealey (Steve Key) the anti-depressant medication’s manufacturer. If the attraction between Connie and Tristan can be attributed to the medication can Dr. James’ failure to establish a significant relationship with Toby a result of her not treating her depression in a proactive fashion?

One wishes to care more for Connie and Tristan and it is not immediately obvious why this does not happen but it appears to be something director David Cromer should have more assiduously addressed. This lack of the ability to connect in any meaningful way with the play’s principals leaves “The Effect” with a less than satisfying effect on the audience.

There is an extended and completely gratuitous sex scene between Connie and Tristan that occurs not only in an on-stage bed (upstage) but is projected on one (sometimes two) areas of Marsha Ginsberg’s versatile set. This scene adds nothing to the progress of the action and the decision to include it is another interesting choice made by the playwright and the creative team. Maybe the audience is part of a clinical trial about having salacious and/or voyeuristic tendencies.

More details about the human brain (like those outlined in “Super Brain” by Deepak Chopra and Rudolph E. Tanzi) would have heightened Ms. Prebble’s premise. Despite this, the play is an interesting exploration into the vicissitudes of love and its provenance and should be seen in order to make up your own mind about its effect on you as an audience member.