Director Benjamin Henson says it's not so much our hearts that Prebble's concerned with but our brains.
"She wants to know what makes us [ourselves] at a time when technology is moving faster than we can stop to think about the implications of it," he says, sitting in a rehearsal room surrounded by medical paraphernalia. "She's saying, 'let's start talking about this now' - what makes us human and the kinds of places the 'artificial additions' to our lives may take us to in the future."
The advantage of being in the audience is that we get to observe Tristan and Connie as well as the doctors watching them and the personal issues, and professional concerns they're grappling with.
So is the theatre the right place to have these types of discussions? Absolutely, say Henson, Lawrence and Watterson. After all, it's a distraction-free environment which encourages the audience to sit back, concentrate and reflect on the various points of view expressed by the characters.
"What's good about the piece is that it doesn't make its own viewpoint clear because it recognises that the discussions around this are complex," says Henson. "It's a very back and forth debate and we get to experience the discussions through a very human lens."
And those characters have disparate views. Irving's Dr Lorna James experiences depression but refuses medication, saying her condition might be beneficial. Henson says he finds the line, 'what if depression is a useful pain, crying out to you to change your life?' particularly evocative.
Lawrence, seen recently playing Victoria in TV's Why Does Love? about the Dance Exponents, says Connie is a character who also advocates caution and seeks answers to all her questions. She points out that the attraction begins before they start the trial but Connie fears it's heightened by the medication.
"And then there's a further complication; they don't know whether they are on a placebo."
Watterson, last on stage in Pop-up Globe's Twelfth Night, says he appreciates the opportunity a play like The Effect provides to test out ideas.
Lest you believe those ideas don't apply to this part of the world, Henson says we should think again. During research for The Effect, Henson and the cast discovered there are some 500 clinical trials going on in NZ.
What: The Effect
Where & when: Loft at Q Theatre, Tuesday - Saturday, August 12