The city has a heartbeat...and they just stepped into its veins.

It started with a hijacking.

When two runaway teens stole Jason Murich's car, they dragged him into a high-speed chase through the streets of L.A. But when the roads ran out, the only place left to hide was underground.

Beneath the city lay a world of crumbling tunnels, buried secrets, and something far more dangerous than police sirens.

And as the three descended deeper, Jason began to realize—they weren't just running from something—they were running toward it.

And the further down they went...the harder it became to crawl back up.