Every runner knows the moment when everything clicks.

When your legs lock into a rhythm, the aches float away and doubts fade.

Replaced by a feeling of euphoria.

It's why you lace up at dawn.

Why little rain doesn't stop you.

Why one run turns into a habit.

So next time you go for a run, chase that runs high.

Learn more about running and go wild at puma.com.

Welcome to the 2020 True Crime Vault, where heart-stopping headlines come to life.

What do you see in this mugshot?

I see somebody who just committed a murder.

That's why there's a mugshot.

You have a kid who believes in Santa Claus and the Easter Bunny, but...

He's now standing accused of murder.

Not just any kid, but his very own son.

He was sitting there with shackles on, belted, handcuffed, like, unbelievable.

Tonight, in all new 2020, the little boy convicted of killing his father's pregnant fiance.

We arrested an 11-year-old boy because he put his shotgun to the back of somebody's head and pulled the trigger.

An 11-year-old who police say loaded his shotgun then shot her in the back of the head.

The world's youngest monster.

And that fueled the media frenzy.

Child killer, who may never know freedom again.

...