The Kol Nidre is the prayer recited at the start of Yom Kippur, the Jewish Day of Atonement. This plea for absolution from oaths sworn, but not honored, may seem of small necessity in our tolerant society, but its import was very immediate for the 500,000 Spanish Jews who, in 1391 and after, were given the choice of converting to Christianity or suffering persecution at the hands of the newly appointed Inquisition.

Allegedly based on a true story, Conviction recounts the crisis of a Catholic priest executed for heresy in 1486, whose crimes against a state-sanctioned religion might have withered in obscurity but for an Israeli scholar in 1962 attempting to steal the 500-year-old dossier from the Archivo Hist�"rico Nacional in Madrid. The inquiry into the motives behind this abortive theft reveals a tale of star-crossed lovers, long-buried secrets, double lives and agonizing risk, as detailed in the confession of a priest named Andrés Gonzáles, who, one fatal day, succumbed to the lure of the bewitching conversa Ysabel and the childhood memories awakened by her family's illegal worship.

Fans of mystery-suspense literature will likely guess the outcome of this doomed adventure after the first 15 minutes: Yes, Andrés is himself a converso, he and Ysabel marry, have a son, are betrayed and the fate of their child erased from memory. Cassock-ripping romance is not the goal of playwright Oren Neeman, however, nor of Yonatan Ben Nachum, from whose novel this play has been adapted. While Andrés struggles to reconcile the spiritual conflicts that torment his soul as fiercely as the threat of exposure and certain death, his exploration of warring faiths lead him to renounce, not Jesus, but those who commit inhumane deeds in His name.

Generating empathy for a 15th-century theological argument is a hefty task for a single actor, even assisted by a text both incisive and evocative in its imagery, but under the direction of Kevin Hart, Ami Dayan shifts effortlessly between his various roles—chiefly, the smug archivo official and the vulnerable Andrés—to paint a very human picture of this humble martyr's excruciation and ecstasy. His portrayal is enhanced by Jon Sousa and Yossi Green's score of Spanish guitar incidental music, its complex harmonies suggesting inner turmoil as intense as the serenity invoked by the orderly script of Fr. Andrés journal projected on the spartan stage.