I never expected to repeat the experience of five years ago: after a revolution that deposed the tyrant, I go back to his jails?

The memories come back to me, all the details of imprisonment; the skills of sleeping on the floor, nine men in a six-by-12-foot (two-by-four-metre) cell, the songs of prison, the conversations. But I absolutely can't remember how I used to keep my glasses safe while I slept.

They have been stepped on three times already today. I suddenly realise they're the same glasses that were with me in my last imprisonment; the one for supporting the Egyptian judiciary in 2006. And that I am locked up, again pending trial, again on a set of loose and flimsy charges – the one difference is that instead of the state security prosecutor we have the military prosecutor – a change in keeping with the military moment we're living now.

Last time my imprisonment was shared with 50 colleagues from the "Kifaya" movement. This time, I'm alone, in a cell with eight men who shouldn't be here; poor, helpless, unjustly held – the guilty among them and the innocent.

As soon as they learned I was one of the "young people of the revolution" they started to curse out the revolution and how it had failed to clean up the ministry of the interior. I spend my first two days listening to stories of torture at the hands of a police force that insists on not being reformed; that takes out its defeat on the bodies of the poor and the helpless.

From their stories I discover the truth of the great achievements of the "return of security" to our streets. Two of my cellmates are first-timers, ordinary young men without an atom of violence in them. And their crime? Armed gangster formations. Yes; Abu Malek alone is an armed gangster formation of one. Now I know what the ministry of the interior means when it regales us every day with news of the discovery and arrest of armed gangsters. We can congratulate ourselves on the return of security.

In the few hours that sunlight enters the dark cell we read what a past cellmate has inscribed on the walls in an elegant Arabic calligraphy.

Four walls covered from floor to ceiling in Qur'anic verses and prayers and invocations and reflections. And what reads like a powerful desire to repent.

Next day we discover, in a low corner, the date of execution of our cellmate of the past. Our tears conquer us.

The guilty make plans for repentance. What can the innocent do?

My thoughts wander as I listen to the radio. I hear the speech of the general as he inaugurates the tallest flagpost in the world – which will surely break all records. I wonder: does pushing the name of the martyr Mina Danial as one of those "accused of instigation" in my case break a record in insolence? They must be the first who murder a man and not only walk in his funeral but spit on his body and accuse it of a crime. Or perhaps this cell could break a record in the number of cockroaches in a prison cell? Abu Malek interrupts my thoughts: "I swear by God if this revolution doesn't do something radical about injustice it will sink without a trace."

This article was written by Alaa Abd El Fattah on 1 November 2011 from cell No 19, the Appeals Prison, Bab el-Khalq, Cairo. It is being published in Arabic by the Egyptian newspaper Al Shorouk and in English by the Guardian.