1A (alternative)
Momentarily stunned I stared at the envelope. Was this simply a continuation of my hellishly bad day? Some unwanted interaction from an impolite oddball? I could feel my exhausted mind beginning to wander off. It didn't want to deal with a situation like this. What would be inside? Some deranged paranoid rantings? A threatening letter? A love letter? A turd? A turd squashed flat in a folded sheet of paper, making a pattern of something; something that might look like a butterfly; like one of those pictures they show you at the psychiatrist.

I rubbed my eyes. I really was tired.

Concentrate Jake. Think!

I ran my fingers along either side of the envelope. It felt thin and papery. No turd. That was something. But how did this person know my name?
Only one way to find out Jake.
I opened the envelope, careful not to touch the gummy bit which pulled apart easily, as if it had been freshly licked. Inside, was another letter. And another envelope.
I started with the letter. It was printed.

Dear Jake. Follow these instruction precisely.
1.Get off at the next platform
2 Sit on the bench next to the vending machine.
3 Wait for the next train to arrive. A man will alight and sit next to you.
4 Give this man the envelope provided, UNOPENED.
5 Immediately board the train before it leaves.
6 Forget this ever happened.
Failure to follow these instructions will result in your death.

Over the tannoy a mechanical voice announced the next station. Automatically I stood up.

As the train began to slow I stared at the new envelope. It was unmarked and made of a thicker higher quality paper than mine had been. It was hard to know what to feel. Should I be excited? Scared? After a few moments I decided on angry. I do not like being to told what to do, especially when it's backed by a death threat and CAPITAL LETTERS on cheap paper.

I walked briskly to the toilet cubicle, opened it, locked myself in and, as the train came juddering to an awkward stop, tore open the second envelope...