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A digital intruder has been watching Hannah.

You look good in blonde hair.

Threatening her.

Stalking you has its benefits.

We will show the world who you really are.

Even impersonating her.

Someone else is in my account and has changed my password.

This anonymous person has invaded Hannah's life.

I no longer know who I can trust.

I'm scared to leave the house, scared to open my phone, afraid of what I'll see.

And evaded the police, staying in the shadows.

The longevity in the scope of this is unusual.

Until now, I'm Carol Cadwalader, an investigative journalist.

Officially, Hannah is my ex-stepdaughter.

That sounds like I've been removed from your life.

I went out with her dad, Dave, a million years ago,

so I've known her since she was seven.

When all this was happening to Hannah,

I was busy working on the most all-consuming story I've ever done.

The Cambridge Analytica Facebook story. She has been working non-stop. It's been four years

since Hannah first opened up to me, and since then, we've been trying to unravel this story

...