The first thing we noticed when we opened the file were the many empty lines below the sentence. After a closer look, it turned out that there were tab spaces in many of the seemingly empty lines.

The first thought was that the tabs and line feeds represent a 01 bit pattern. But unfortunately a simple replacement of the tabs with a 1 and the line feeds with a 0 did not bring any result for the time being.

Another approach was the offered sentence. This was a quote from John le Carré a former MI5 and MI6 agent. We spent a lot of time to collect more information about John le Carré etc.. Until the first clue appeared saying not to focus on the sentence.

So we started to rethink the 01 bit pattern approach. What finally led to the solution of the challenge.

We took the hexdump of the file and replaced all 0A hex values (tab spaces) with 0 and all 09 hex values (line feeds) with 1. Then we tried to convert them by different bit patterns from 3-bit to 8-bit into ASCII characters. Still without success.

On the way brought us the hint that the flag consists only of capital letters. At the same time the hint appeared that it is a 5 bit encoding. So we searched a bit and found the Baudot code. This code was used for telegraphs. A conversion with a Baudot converter brought the following result.

A bit confusing but after a closer look a pattern appeared. A kind of alphabet. And already we had the flag in our hands.

**TMCTF{PUNCH.CARDS.ARE.DEAD.NOW}**