Dateline: Unforgettable

When Britney Ujlaky disappears, a small Nevada town bands together to track down an unknown cowboy.

An apparent home invasion in Minnesota leaves Heidi Firkus dead and her husband hospitalized. For Blayne Alexander, getting to know Heidi through loved ones was a privilege; for investigators, learning about Heidi helps solve the case.

An investigation into the poisoning of Wisconsin mother-of-two Julie Jensen takes a surprising turn when detectives learn that she wrote a letter days before her death pointing to a possible suspect.