Tara Lambert says that when she married her husband, Brandon, and became stepmom two his two daughters, she became close friends with his ex and mother of his children, Kellie Cooke. She claims she and Cooke were confidantes and that she was in the delivery room when Cooke delivered her two youngest children.

TELL DR. PHIL YOUR STORY: Are you involved in a story that has made the headlines?

However, things turned sour between Lambert and Cooke -- leading to the model turned suburban stepmom hiring a hitman. Did she really want her former best friend dead? See what she says in the video above from an exclusive interview with Dr. Phil airing Monday.

WATCH: Model Turned Suburban Stepmom Convicted In Murder-For-Hire Plot

After a trial and overturned conviction, Lambert pleaded guilty to conspiracy to commit aggravated murder and was sentenced to five years in prison.

On Monday’s episode of Dr. Phil, the victim, Kellie Cooke, and the woman enlisted to help Tara find a hit man, sit down together for the first time in an exclusive interview to tell their stories. And on Tuesday, see video of the undercover police sting that led to Lambert’s arrest. Check here to see where you can watch.

‘How Did You Go From Being Best Friends … To Her Wanting You Dead?’ Dr. Phil Asks Guest