(Want to get this briefing by email? Here’s the sign-up.)

Good morning.

Here’s what you need to know:

• Las Vegas puzzle endures.

In one mass shooting after another, gunmen left evidence of their motives. But days after the mass shooting by Stephen Paddock, what drove him remains a mystery.

Here is the latest in the investigation. Late Thursday, the coroner released the names of the 58 victims, ranging in age from 20 to 67. We’re collecting their stories.

And the National Rifle Association added an unlikely voice to the growing call for tighter restrictions on a device that allowed Mr. Paddock to fire hundreds of rounds a minute.