Sherlock Holmes S05E01 STORY part 2

Mycroft : I have to  leave . going with the prime minister crew
Mycroft left
Watson: so now what you thinking ?
Sherlock glancing at the file. There some information about the scientists servant who was working at the scientists house since long time . his native address was that country of which the courier has arrived.
Sherlock: let's go. We have leave.
Watson : what happen where we were going?
Sherlock came out from 221B and called for a taxi.
Sherlock: airport
Chauffer man: OK sir
Watson : sherlock what about luggage and other stuff. I have some appointments tommorow.
Sherlock : Its a matter of world security and I think the servant have some connection. Let's find him.
Watson: OK
They reach airport. As moira was ready there with the passport of both of them.
Now at plane
Watson: how moira came to know we were heading to airport.
Sherlock : I texted her.
Watson : how you are going to find that servant?
Sherlock : don't know!!!
They reached to that country and asking for taxi.
Sherlock : did you notice that someone stalking us from airport ??
Watson: no (turned around)
Sherlock: don't turn just walk faster.
They found taxi and moved towards the hotel.after some distance there was none stalking them.they reached the hotel.
Sherlock : (on mobile) have you got the address of the servant?
Mycroft : I m still searching.
Sherlock : I think he was the one who sent the tickets and stole marys letter and in the morning he was following us.
Mycroft : ok give me some more time.( call ended)
Watson : but why he is not coming in front of us and why stalking us?
Sherlock : he was just afraid of police for killing scientists and stealing the bombs formula. He was stalking just to confirm.
Watson : so now what ? What you are going to do next?
Sherlock : let's have some walk
They went outside the hotel. Didn't asked for any taxi. After long distance walking, at desolate place a wierd looking man came in front of them and gave a piece of paper and sudden vanished from that place.
Watson: what's that ? Who was that ? How he vanished from here?
Sherlock : its just a blank paper. He was servant. Let's go back to hotel.
Watson : ok
Sherlock still looking at that piece of paper. Trying to find the message on this. they the reached the hotel.
Mycroft : ( on phone) you can come to function. I am sending the passes.
Sherlock : No I don't have time ? I m busy( call ended)
At night ,
Watson : Sherlock go and have a nap its very late now
Sherlock : you go and sleep
Watson : why you are not listening to me just and sleep ( and pulled that blank paper from the Sherlock's hand)
Sherlock : ok I will sleep for sometime
Watson put that paper above the fireplace.
At morning Sherlock came and raises that blank paper there is something faintly visible. Sherlock taught and there clicked something to him he took that letter near the candle and now everything was crystal clear.
Watson: what you doing ? Why you burning the paper?
Sherlock : thank you very much . you solved the mystery of letter
Watson : how I did ?
Sherlock : get ready we need to go. I will tell in the taxi.
Watson : ok ( glancing at the paper there is written there SAVE PM)
They got ready and came out from hotel. And asked for taxi.
Watson : now can you tell me how I done that!!
Sherlock : you took that letter from my hands and put above the  fireplace .In the morning when I raised that letter there was something faintly visible and I understood that because of heat it was visible. It was written by the juice of onions which is invisible after writing.
Watson : clever.!! Scientists had servant as clever as he was .
Sherlock : yeah true so
They reached the summit where the meeting to be took place . Sherlock observed the security very carefully. He came to conclusion that its quit impossible to  roll in with bomb .
Watson : I think its impossible.
Sherlock : yeah I know
Watson : someone has kept that earlier.
Sherlock : may be