Movies about the mentally ill tend to render them in cute, charming strokes — with only the occasional blast of ugly to remind us, “Oh yeah, this gorgeous, lovelorn soul is still CRAZY.”

And “Silver Linings Playbook” has a hint of that. You cast Bradley Cooper as a mentally ill man who probably got out of the psychiatric ward a bit too early, and Jennifer Lawrence as a young cop’s widow who isn’t really coping with that fact well and the Hollywood ending is written all over it.

“They’re too pretty to be seriously ill.”

But Cooper gives his most natural, affecting and compelling performance yet as Pat, a divorced ex-school teacher who won’t accept the fact that he’s divorced, or that the school system would never rehire him. People may duck him in amusing ways, but the message is clear — he’s dangerous.

And as Tiffany, Lawrence (“Winter’s Bone”) makes us forget her dewy youth just minutes into her brittle, biting turn as a woman whose unbalanced rage is even more cleverly concealed than Pat’s.

Pat’s mom (Jacki Weaver of “Animal Kingdom”) is the one who has the faith that her son is better, that he’d be better off at home in Philadelphia. His sports-nut dad (Robert DeNiro, perfect) isn’t so sure. When Pat pulls a plastic garbage bag over his sweatshirt so that he can jog and lose weight faster, Dad seems to have a point.

“I’m getting really fit for Nikki,” the son explains. That’s the ex-wife Pat expects to win back.

Others aren’t that delusional, which is why the shrill Veronica (Julia Stiles) nags her husband (John Ortiz) to invite Pat, whom she fears and despises, to dinner. She wants the mentally unstable guy to meet her mentally unstable sister, Tiffany. Is Veronica an idiot?

But that jaw-droppingly awkward dinner meeting is where this David O. Russell (“The Fighter”) film takes off. The sparks fly between these two — and not necessarily romantic ones. They have an easy rapport, joking and comparing medications. But Pat’s unshakable belief that he’s getting the ex, who has a restraining order on him, back, makes him seem touchier, scarier and further gone than Tiffany. Until testy Tiffany takes a moment to assure us that’s a much tighter race than you’d expect.

Pat has these little mantras he picked up from group therapy and psychological counseling. “Excelsoir!” he shouts at random moments when he needs some affirmation.

“If you stay positive, you have a shot at a silver lining.” That’s what he’s looking for in all this. Tiffany?

“I don’t get what I want, OK?” Her volatility is a fearsome thing, especially when she feels she’s in a contest. “You think that I’m crazier than you.”

The director, famous for his own off-camera temper, deftly balances each amusing encounter — threatening to bring matters to an ugly head, or deepen the connection between these two disconnected people — with tragic revelations. In film and in fiction there’s always a glib cause and effect with mental illness — this led directly to that. We get a little of that here as we’re given the back story, and we meet enough relatives to see the trees these two fun but dysfunctional apples fell from.

Anupam Kher is the cute psychotherapist. Shea Whigham is Pat’s successful, more functional brother, a performance that suggests a less sensitive guy who unthinkingly channeled Dad’s Philadelphia Eagles obsession into a safer corner of his psyche. And Chris Tucker turns up as a funny, dialed-down mental patient pal of Pat’s who can seem the most normal of all of them. But he lets us sense that coiled up inside that guy is a motor-mouthed maniac, the Tucker of “Rush Hour”, straining to get out.

“Silver Linings Playbook,” adapted from Matthew Quick’s novel, is a ringing endorsement of “the talking cure,” two people whose professional counseling is nothing compared to the ways they challenge each other and themselves to get better, each to make a better impression on the other. Not easily, and not right away, of course. We take it as a matter of faith that whatever happens, the “Hollywood ending” this film delivers will be unexpected, even if we — like the characters — have to look extra hard for that silver lining.

MPAA Rating: R, for language and some sexual content/nudity

Cast: Bradley Cooper, Jennifer Lawrence, Robert DeNiro, Jacki Weaver, Shea Whigham, Julia Stiles, Chris Tucker

Credits: Directed by David O. Russell.  A Weinstein Co. release.

Running time: 1:55