I am currently being held in prison under false accusation of murder, but do not worry about that, my lawyer will soon make things straight. If I write to you today is for another case: my cellmate just died last night while sleeping. It’s not that strange though, as he was an old man, somewhat deranged and he spent much time in prison. However, he told me a few days ago that he found a valuable secret, and he would keep it to himself. I thought I should investigate to find out about that secret, and just before they carried his body away, I managed to take his personal diary.
I tried making sense of his writings, and one thing I spotted is that he made great deal of a new friend of his, related to the secret. Here are a few examples:
In case it helps, here is his puzzle #15:
( There’s a note on this page I did not catch on my photograph: A=1 )
And let me provide a transcript of the first two encrypted messages (can’t type the rest)
In the diary, there are a ton of other games, cryptic messages, wordplays, etc. He loved talking in riddles and that would make people uncomfortable. For instance, the first day I arrived in the prison, he gave me this:
Well, that's not my cup of tea. And that's nothing compared to his diary. By the way, that contained an extra sheet: one piece of London's tube map (why would he need it?) with an ugly drawing on the reverse.
If you help me find out I promise to share the value of that "secret". But hurry! I'll soon get out of prison, and you may need me here for new clues. I'd really like to find his secret.
Sincerely, Jack P.
I see people are making good progress here, but it looks like that tube map was important. It must have some use in understanding the puzzles.
Sorry to say the same thing again, but it really looks like the map is important, and I feel there still is something in it.