You're back home after four years working abroad, new husband in tow.

You're keen to find a place of your own. But for now you're crashing in your big brother's spare room.

That's when you meet the man next door.

He's the head teacher at the local school. Twice your age. Extraordinarily attractive. You find yourself watching him.

All the time.

But you never dreamed that your innocent crush might become a deadly obsession.

Or that someone is watching you.