Shadows

When Scarlett is taken from her home and thrown in the back of a van, I guess you could say she got a bit of a shock. At the realisation her kidnappers got the wrong girl, they decide to cover up their mistake to save their own necks, and take her on a journey she never wanted to go on.
They're there, but never fully in sight.
They're listening, but make no sound.
They're alive, but don't strictly exist.
They follow you everywhere you go.
They see everything you do.
Those four boys were merely shadows.