The round, lavishly painted floor of Neil Patel’s set for Edgardo Mine suggests the Sistine Chapel flipped like a flapjack — which makes sense, since the Holy See does get turned upside down in the course of Alfred Uhry’s play, the papal states dissolving into modern Italy. Set in 19th-century Rome and Bologna, the work, which is getting its world premiere at Hartford Stage, tells the story of Edgardo Mortara, the Elián González of his day, who in 1858, at the age of six, was stolen from his Jewish family on orders of the pope.

It seems the infant Edgardo, one of eight children of a Bolognese Jewish merchant, had been baptized in infancy by a Catholic serving girl who, fearful he would die of a fever, didn’t want him excluded from Heaven. When whispers of this reached Pope Pius IX, he invoked the law that no Christian child could reside in a Jewish home, and the local constabulary turned up in the night to whisk the boy off to " Pio Nono, " as the play’s avuncular if absolutist pope calls himself. Edgardo was never returned to his parents and in fact became a Catholic priest. But the international hue and cry over his kidnapping became a significant contributor to the pope’s loss of temporal power in Italy.

It’s a fascinating subject for a play: there’s the human drama of familial separation, not to mention the didactic struggle between religious people convinced theirs is the " one true God. " But Uhry’s 90-minute play, though theatrical, is surprisingly superficial. Based on the (I presume) weightier 1997 book The Kidnapping of Edgardo Mortara, by Brown University professor David Kertzer, Edgardo Mine skims the surface of the incident and its repercussions. Uhry, the Pulitzer-winning author of Driving Miss Daisy, seems more intent on making a slyly entertaining hambone of the pope than exploring the Brechtian possibilities and troubling implications of the material. Uhry also wrote the book for the controversial Broadway musical Parade, which is likewise based on a nasty historical incident: the lynching of Jewish factory manager Leo Frank in 1915 Atlanta. There’s no music in Edgardo Mine, but the scenario is skeletal enough to make room for a score.

At Hartford Stage, where the play’s minimalist pageantry and ironic humor are well exploited by director Doug Hughes, Brian Murray (looking like Cardinal Law in full regalia) makes his entrance on high, solemnly stepping down a balcony of stairs. Reaching the middle height of the three-tiered set, he drops his outstretched arms to rest his holy hands on a banister, breaks into a relaxed grin, and proceeds to charm the audience — as, indeed, he will little Edgardo before attempting to seduce the frantic, powerless parents. " Call me Nono, " he purrs, urging us to think of him as " somebody comfortable and comforting. " Later, pressured to give up Edgardo (whom he claims God has personally chosen), he will lose his temper, vilifying " this great thumping modern world " and thundering against the " synagogue of Satan " as he grips his power with white knuckles. But by and large, Uhry makes this dangerous Defender of the Faith too lovable, and accomplished actor Murray plays him to the grandfatherly hilt, showboating about the stage pitching the audience and manipulating the action like some mitered Stage Manager in a Vatican version of Our Town.

Indeed, one the play’s theatrical devices is to run crucial scenes in the pope’s account followed by the version of Edgardo’s bereft and infuriated mother, who’s sufficiently unimpressed by Pius’s power and position that she tells him to go to hell and refers to his papal raiment as a " party dress. " For all that Randy Graff as the fighting mom (in Uhry’s re-creation the pope’s chief adversary) is touching as well as smart-alecky, the he said/she said approach can get cute (though not, perhaps, as cute as Jesse Schwartz’s diminutive, self-possessed Edgardo). Uhry seems less interested in the heartache or the historical ramifications of the Mortara incident than he is in forging a pithy Pirandellian entertainment out of it. In Michael Frayn’s Copenhagen, which also offers instant replay, the scientific exactitude of memory is called into question; here it’s all about spin.

The intertwined stories of Edgardo Mortara, forcibly robbed of his family but imbued with a faith, and Pope Pius IX, his outrageous act and arrogance rooted in true belief, are compelling enough to fuel Edgardo Mine. But I can’t help wishing the play dug deeper rather than moved so fast.