Greta

Isabelle Huppert transitions from stalked to stalker in Greta, a role that doesn’t allow her the same emotional complexity that marked her Oscar-nominated role in Elle.

This psychological thriller makes slight tweaks to a familiar formula in a muddled effort from veteran Irish director Neil Jordan (The Crying Game) that at least grants the versatile French star an amusing opportunity to chew the scenery in the title role.

The film opens with Frances (Chloe Grace Moretz), a server at an upscale Tribeca eatery, finding a handbag on the subway. The following day, against the advice of her impulsive roommate (Maika Monroe), she traces the contents to Greta and returns it.

When she’s invited inside Greta’s house for coffee, Frances is unaware of the mistakes she’s about to make. Falling for Greta’s sad-sack tale of loneliness and abandonment, she exchanges phone numbers and offers to help Greta pick out a rescue dog from the shelter. Coming from a fractured family herself, Frances views Greta as a surrogate mother of sorts.

That vulnerability only sets the hook for Greta, who later reveals deranged behavior and a manipulative obsession with companionship. As she wonders about the endgame, the inability of Frances to flee Greta’s life puts her in greater peril.

For a while, Greta effectively generates solid suspense by preying upon common fears in the social-media age, such as the importance of guarding your privacy online and the inability of authorities to step in on your behalf.

Although it makes some logical stumbles, the taut screenplay by Jordan and Ray Wright (Case 39) benefits at first from the intriguing dynamics between Greta and Frances as we piece together details about their backgrounds and motives.

However, the film loses its momentum drastically in the second half as the plot twists become more far-fetched and the emotional stakes dwindle. The final act, including a somewhat clever finale, can’t seem to decide whether it’s a more of a psychosexual slasher flick or a macabre farce, and becomes caught in the middle.

Despite its gender-reversed premise, the eye-rolling result bows to mainstream genre conventions more than carving its own niche. As a less intended consequence, perhaps it will make potential Good Samaritans think twice.

Rated R, 98 minutes.