When it matters most, the Playcrafters Barn Theatre gets A Miracle Worker right, and does emotional justice to author William Gibson's tale of Annie Sullivan (Cayte McClanathan) teaching the blind, deaf, and mute Helen Keller (Emma Terronez) how to communicate through sign language. The scenes shared by McClanathan and Terronez are powerful, and their chemistry palpable, in Annie's fight to force young Helen to learn, and Helen's stubborn efforts to resist. But in truth, Saturday's performance didn't really find its footing until McClanathan and Terronez first shared the stage about halfway through Act I.