'The Disappearance of Susan Cox Powell' Special Reveals a New Theory (VIDEO)

Meredith Jacobs
Exclusive NBC

A disturbing family secret may lead to answers about the disappearance of 28-year-old Susan Cox Powell.

TV Insider has an exclusive first look at Oxygen's The Disappearance of Susan Cox Powell, a two-night event airing Saturday, May 4, and Sunday, May 5, at 7/6c.

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One has already been optioned for a Hollywood movie.

Susan disappeared from her suburban home in West Valley City, Utah in 2009, and husband Josh's alibi was a strange one. He said that, after she went to bed, he took their sons on a spontaneous camping trip during a winter blizzard. More than two years later, he took his own life and the lives of his sons.

In this four-hour series, investigative journalist Stephanie Bauer dissects the Powells' marriage, "taking a stark look at the topic of domestic violence and emotional abuse while revealing a complex Powell family dynamic." When her relationship with Josh began, his father, Steven Powell, became obsessed with her.

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The Lifetime special brings the former missing persons and victims' advocates together with other survivors of abduction.

The special includes Steven's home videos, as seen in the sneak peek below, new evidence, and a new theory as to what happened to Susan.

"Steven Powell was narcissistic, very self-absorbed, out of touch with reality," lead detective Ellis Maxwell says. "He was under the impression that anytime he was with Susan or saw Susan, that she was hitting on him, that she was interested in him."

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The prosecutor turned investigator tries to help families find closure.

Watch the video to see more from Maxwell and comments from the Cox family attorney Anne Bremner.

The Disappearance of Susan Cox Powell, Saturday, May 4, and Sunday, May 5, 7/6c, Oxygen