It's twenty hours to landing. A lot can happen in twenty hours . . .

You're on board the first non-stop flight from London to Sydney. It's a landmark journey, and the world is watching.

Shortly after take-off, you receive a chilling anonymous note.

There are people on this plane intent on bringing it down - and you're the key to their plan.

You'd never help them, even if your life depended on it.

But they have your daughter . . . So now you have to choose.