The film stars Isabelle Huppert, Chloë Grace Moretz, Maika Monroe, Colm Feore and Stephen Rea, and follows a young woman as she befriends a lonely widow who becomes disturbingly obsessed with her.

Frances McCullen, a young waitress living in New York City, finds a handbag on a subway train; the ID inside the bag reveals the owner to be a Greta Hideg.

Frances meets a former lover of Nicola's, and discovers that Greta is Hungarian and not French, and that her sadistic behavior led to her daughter's suicide four years ago.

Erica suggests Frances lie to Greta about leaving town to spend time with her father, and instead secretly hide in their apartment for a while.

When Frances is released from the chest, she finds clothing and IDs of other young women Greta had previously kidnapped, implying that she has killed all of them.

Cody begins to realize there's a secret room nearby, but his discovery is cut short when Greta plunges a syringe into his neck, then shoots him with his own gun.

Erica and Frances lock Greta's unconscious body in the toy chest, using an Eiffel Tower trinket as a makeshift latch.

In May 2017, it was announced that Isabelle Huppert and Chloë Grace Moretz had signed to star in the film, then titled The Widow.

[7] Shortly after, Focus Features beat out studios including Netflix, Lionsgate and Neon to acquire North American, Chinese, Australian and New Zealand distribution rights to the film; the company and its parent Universal Pictures had also purchased UK distribution rights prior.

The website's consensus reads: "A bonkers B movie that's occasionally elevated by its A-list talent, Greta dives headlong into camp and struggles to stay afloat.

[11] In the United States and Canada, Greta was released alongside A Madea Family Funeral, and was projected to gross around $6 million from 2,000 theaters in its opening weekend.