There’s a bold concept behind BackStage Theatre Company’s production of Euripides’ classic: Jason is played by deaf actor Chris Lopez while the scorned, vengeful Medea can hear. The conceit pays off intermittently in Michael Pacas’s staging. Using the two children as ASL translators for their parents’ battles makes it clear they’re tragic pawns; it’s especially poignant when the daughter delivers Jason’s encomiums to his son–praise that she’s denied. Karen Yates’s performance as Medea blends slyness with feral passion, and Lopez’s anguish at the end is chilling. But the supporting cast tends to be bland, and the pace is slow: swifter action that feels more inexorable would have driven home the horrors wrought by blind hate and pride. Through 7/23: Thu-Sat 8 PM, Sun 3 PM, Chopin Theatre, 1543 W. Division, 312-683-5347, $12-$15.