It’s an odd niche, I’ll admit. But I’ve always been fascinated by the origin stories of professions.

The art of criminal investigation unfolding in “The Name of the Rose,” Medieval legal defense arising in “The Advocate,” medicine moving out of Dark Ages superstition in “The Physician” — all were absorbing period pieces with whose antagonists are, in various ways, poking around in the dark or making it up as they go along.

In “Three Christs,” group therapy was a new thing when an academic decided to try it out of three schizophrenic men whose delusions had them thinking they were Jesus at the Ypsilanti, Michigan mental hospital where they were housed.

But electro-shock therapy and drugs were getting them nowhere. And Dr. Alan Stone (Richard Gere) thinks a little empathy, from him and them to each other, might help. He is drawn to schizophrenia because of the overriding characteristic of those suffering from this illness — “because they’re so lonely.”

Director and co-writer Jon Avnet (“Fried Green Tomatoes,” “Red Corner”) conjures up a too-conventional treatment of this true story, one that devolves from quiet character study into full-blown, over-the-top “star vehicle” in its last act.

But very good casting, and committed work from the “Christs” in question — Peter Dinklage, Walton Goggins and Bradley Whitford — make this drama just uplifting enough to come off.

It’s a heavily-fictionalized version of the case-study “The Three Christs of Ypsilanti by Milton Rokeach. Gere plays a version of the psychotherapist, who takes a job at a state hospital to do some research and publish. As he’s already published criticisms of such institutions as “warehouses” or “bureaucratic, unfeeling conformity.”

The director of the place (Kevin Pollack) is not amused. The state director (Stephen Root) is willing to give Stone a little latitude.

Because Stone has stumbled into the fact that there are “three Cinderellas, two Eisenhowers (it’s 1960) and one Duke Ellington” among their 4100 patients. And the three fellows who think they’re Jesus have his attention.

Joseph (Dinklage) is “Jesus Christ, courageous one am I,” an opera buff who affects an English accent.

Clyde (Whitford) is “Christ, but I’m not from Nazareth.” He’s constantly singing TV commercial jingles, constantly showering, incessantly complaining about a stench only he smells.

Leon (Goggins) is the belligerent, scary one. “Address me by my RIGHTEOUS name, God!” He is oversexed and cannot stop talking about Dr. Stone’s new assistant, Becky (Charlotte Hope).

Stone figures he can “put the three of them in a room,” get them singing, talking and playing cards,” which might help them “give up their delusions.”

Is he delusional? Every time the lights dim in the place, “Shocky Boy,” a trigger happy therapist “managing” the unruly, has electro-shocked another victim.

The conventional touches — and there are many — are the problems his obsession creates for Dr. Stone at home (Julianna Margulies plays his chemist-wife), the tug of war over the patients with Dr. Orbus (Pollack) and the shortcuts that Stone takes to try and “speed up” the process.

It being 1960, dabbling in LSD-driven self-awareness is on the table.

And “progress” is measured in civility, calms of sanity, sort of “Awakenings” with schizophrenia.

The big boss, the one who scares EVERYbody, is played by four-time Oscar nominee Jane Alexander.

Avnet never lets the picture lapse into “cute,” but there are moments, here and there, that seem off-key or gratuitous. And the third act’s heroics are so formulaic and old fashioned that you’d think they’d been banished by the ridicule they took in Robert Altman’s movie biz satire “The Player” 25 years ago.

But this cast never lets us feel that the story isn’t in the hands of seasoned pros, that what we understand and feel out of this story isn’t earned, even if it is often expected.

MPAA Rating: R for disturbing material, sexual content and brief drug use

Cast: Richard Gere, Peter Dinklage, Julianna Margulies, Charlotte Hope, Walton Goggins, Bradley Whitford, Kevin Pollack and Jane Alexander

Credits: Directed by Jon Avnet, script by Eric Nazarian and Jon Avnet, based on the book “The Three Christs of Ypsilanti by Milton Rokeach. An IFC release.

Running time: 1:50