When is imitation NOT the sincerest form of flattery? When you’re imitating Alfred Hitchcock, ALL of Alfred Hitchcock’s ouevre in a manic misshapen mess of a thriller meant to be an homage.

“The Master of Suspense” never managed “manic,” recognized it as the enemy of “suspense.” And director Joe Wright (“Atonement,” “Darkest Hour”) surely should have known that, even if playwright, actor and in this case, screenwriter Tracy Letts didn’t.

“The Woman in the Window” is about an agoraphobic movie nut who thinks she’s witnessed a murder in the brownstone across from hers on West 121st Street.

Amy Adams plays Anna, a child psychologist whose “anxiety” pushed her into this isolation. It may have busted up her marriage (Anthony Mackie plays the husband) and landed her in therapy (Letts plays her shrink) and on medication.

The therapy and the meds are really working, as Anna’s going through wine like she’s hydrating with it and neither she nor anyone else around her can believe what she sees or says she’s seen.

And like L.B. Jeffries, Jimmy Stewart’s character in “Rear Window,” she’s become obsessed with the folks within her limited field on view on West 121st street. Those new neighbors? They get ALL of her attention. Maybe that’s a good thing, she tells her therapist.

“People who snoop on their neighbors don’t kill themselves,” she reassures him.

Julianne Moore is Jane Russell, friendly, coming over to give her a scented candle, sip wine and complain about her “tight, controlling” husband. Fred Hechinger is their son, the outgoing Ethan, who is allergic to her Persian cat, Punch.

And the testy guy who crosses the street looking for those two, Alastair? That’s Gary Oldman. He’s just the sort of husband you’d picture as “tight, controlling.” And when Anna sees something happen to Jane through that window, Alastair must have been the fellow holding the knife.

Oldman as a possible psychopathic killer? Kind of on the nose. When Anna makes her accusations, his rants are vintage, pre-Oscar Oldman.

“A drunken, shut-in pill-popping CAT lady!”

Wyatt Russell plays the singer-songwriter Anna rents her basement apartment to, and imposes on and generally worries to death. Brian Tyree Henry is the detective who shows up to patiently investigate her latest accusation and burst of “mania.”

It’s based on a novel by A.J. Finn, and freely acknowledges its “Rear Window” connections (unlike “Disturbia”) by having that as one of the movies Anna watches, along with anything Bogart or Bacall or Clifton Webb made in the black and white ’40s.

Adams gives some interesting wrinkles to a woman who studies the mind and has seen patients, and can’t get a handle on whether or not what she’s seeing or experiencing is real or a product of her guilt-ridden mental breakdown. She knows what’s happening to her, with or without “gaslighting.”

Oldman is sinister enough to make you think he’s giving away the game from the get-go. But there are all these other obvious “tells” in the clumsily “tricky” screenplay.

We can’t be sure of anything, because Wright shoots and cuts this thriller to death. Tilted camera, extreme close-ups and whip-pans, snippets of classic films in Anna’s mind, with Letts’ staccato take on film noir patter, the strident Bernard Hermann Hitchcock strings and Adams amping up the mania, who can believe any of it?

It’s so overdone it’s as if they’re all panicking over the balderdash they figured out — after filming started — they were collectively serving up.

Shortcomings aside, stylistic overkill (Hellloooo Brian DePalma) included, the only real downside to all this is the too-obvious “mystery” is the dishonor it does the filmmaker Wright, Letts & Co. are “paying tribute” to.

Don’t let a bad Hitchock homage scare you away from The Master of Suspense.

MPA Rating: R for violence and language

Cast: Amy Adams, Gary Oldman, Julianne Moore, Wyatt Russell, Fred Hechinger, Brian Tyree Henry, Jennifer Jason Leigh, and Anthony Mackie.

Credits: Directed by Joe Wright, script by Tracy Letts, based on a novel by A.J. Finn. A 20th Century release on Netflix.

Running time: 1:42