'Within 5 Years, Someone Is Dead': Watch Clip from ID Docuseries on Natalia Grace's Adoption-Gone-Wrong

The bizarre story of Natalia Grace, an orphan from Ukraine who was adopted by an Indiana couple, has made headlines around the world.

Michael and Kristine Barnett said when they first adopted Natalia Grace in 2010 they believed they were adopting a 6-year-old girl. Soon after, they claimed they became suspicious of her age, leading to a bombshell claim: that Natalia, who has a form of dwarfism called spondyloepiphyseal, was merely posing as a child — was really an adult woman with sinister intentions.

The Barnetts alleged Natalia tried to harm them and their biological children. They accused the orphan of trying to poison Kristine's coffee and kill her by dragging her towards an electric fence. They also accused her of placing clear thumb tacks on the stairs face up so that they would step on them.

"I promise you within five years someone is dead," Michael Barnett says in the cold open to the first episode of the three-part docuseries, The Curious Case of Natalia Grace, which will debut across three consecutive nights on ID beginning Monday, May 29, airing nightly from 9-11pm ET/PT. (The cold open is shown below.)

"Do you want to give me a word that describes Natalia to me?," says Michael. "Enigma."

"She threatened to stab my sons, drag their bodies outside and bury them underneath the deck," Michael says.

Michael previously told Good Morning America that doctors allegedly treating Natalia told them, "This person is a sociopath. This person is a con artist. You are all in danger."

In 2012, two years after Natalia was adopted by the Barnetts, the couple petitioned Marion County Probate Court to have her age legally changed to 22, changing her birth year from 2003 to 1989.

The following year, the couple moved with their three sons to Canada without her, leaving her alone in an apartment in Lafayette.

The Barnetts, who later divorced, were charged with neglect of a dependent. Prosecutors couldn't charge the couple with neglect of a child because of Natalie's court-ordered age change.

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Natalia testified during Michael's trial saying that she didn't want to live in Lafayette.

"I wanted to be with the Barnetts," she said, the Lafayette Journal & Courier reported. "I wanted to live with them."

Michael was found not guilty of three counts of neglect and conspiracy to commit neglect of a dependent in 2022, the Associated Press reported.

In March, charges against Kristina were dropped, according to WTHR.

The Curious Case of Natalia Grace airs across three consecutive nights on ID beginning Monday, May 29, airing nightly from 9-11 p.m. ET/PT.