(NBC News) — Friday on “Dateline,” following her husband’s sudden death, Kouri Richins, a Utah mother of three, wrote a book to help her children through their grief.

But when investigators dig deeper — she’s charged with murder.

Here is a preview of Andrea Canning’s report:

In the shadow of Park City, Utah — a playground for the rich and famous — sits tranquil Kamas Valley — the perfect place to raise a family. And by all appearances, the Richins family — Eric, Kouri and their three boys had a picture-perfect life there.

Suddenly, tragedy struck in the middle of the night. At just 39 years old, Eric was found dead in his home.

Soon, a family’s private tragedy would become public when Kouri chose a unique way to grieve. She wrote a children’s book, to help her sons grieve.

What happened next was so unbelievable, it seemed everyone was talking about it. It’s a story of secrets, lies, and money.

GREG SKORDAS: This whole case just has so many nuances and so many twists and turns you couldn’t make it up. But that’s why truth is sometimes stranger than fiction.

And it’s not over yet.

Friday on “Dateline: Page Turner,” friends of the couple speak out about the ongoing case. Watch at 10 p.m. on NBC4.