Boy Finds Hatch in Backyard, Then His Father Sees Where It Goes

What is the connection?

Surveying the industrial space, Ben’s mind raced to connect the dots. Rows of locked storage units lined the area, their heavy padlocks gleaming in the sunlight. “This is some kind of storage facility,” Ben concluded. But the question gnawed at him: why would a tunnel lead from their backyard to here? He glanced at Cody, who seemed equally perplexed. Whatever this place was, Ben had the sinking feeling it wasn’t by chance.