'Doubt," the excellent movie that John Patrick Shanley adapted and directed from his Pulitzer- and Tony-winning play, works on many levels. Like the play, the film is set in 1964 in a Catholic church in the Bronx.

Most overtly, the film, now out on DVD (Miramax, $30; Blu-ray, $35), is a mystery concerning whether a young Catholic priest, Father Flynn (Philip Seymour Hoffman), is having an improper relationship with one of his students at the parish school.

His main accuser is the school's principal, Sister Aloysius (Meryl Streep). She eagerly jumps to that conclusion after one of her fellow nuns, a young teacher named Sister James (Amy Adams), confides in her that Father Flynn seems to have "taken an interest" in the 12-year-old boy, who happens to be the school's first and only black student.

"Doubt" is also a meditation on how quickly people make up their minds about things that are not as clear-cut as they appear to be. In addition, "Doubt" offers a richly detailed examination of a particular time and place inside and outside the Catholic Church, on the verge of cultural change.

Sister Aloysius' distrust of Father Flynn is fueled by her dislike of his more progressive approach to Catholicism. She's vehemently old guard in her belief in maintaining strict, even fearful, discipline over her students, and she resents the young priest's more relaxed and friendly demeanor and his liberal ideas. Yet she's also intelligent, with a sharp, biting wit.

Conversely, the priest's liberalism does not extend to the gender hierarchy that exists within the church, particularly the status of priests vs. nuns. In one telling scene, Father Flynn comes to Sister Aloysius' office for a meeting and, without thinking, sits in her chair. Later on, he berates her for pursuing her investigation of him in a manner that violates the church's centuries-old structure.

The setting also evokes the changes in U.S. society brought about by the assassination of President John Kennedy a year earlier and the continued efforts of the civil rights movement, particularly its challenge to school and housing segregation.

In his commentary and in several short documentaries on the disc, Shanley discusses how he transformed his four-character play for the screen. He insisted that the movie be filmed in the neighborhood in which he grew up. He expanded the parts in the film so that audiences actually see students at the school, which makes the allegations against Father Flynn less abstract and more real. And we see the congregation listening to and reacting to the priest's sermons.

Shanley's multidimensional script, which earned an Oscar nomination for best adapted screenplay, gets a brilliant reading from its principal cast members -- all four of whom also received nominations for their work.

To Shanley's credit, "Doubt" as a film remains provocative, challenging and demanding. He provides no easy answers or definitive conclusions to either the broader issues raised or the specific charge leveled by Sister Aloysius against Father Flynn. As an audience, we are buffeted back and forth in our allegiances.

As Shanley told a New York Times interviewer, "I'd like to attack the notion that movies are about certainty, about affirming a political profile and validating what people already believe."

Instead, in "Doubt," Shanley asks us all to think.