Not long after the clashes around Tahrir started a new wall in Qasr Al-Ainy went up. Those that paint the night transformed the oppressive grey, cement blocks just hours after it was built into a cheerful, mocking smiley face.

What was intended as a grim separation between protesters and CSF, became a bright yellow stretch of wall, adorned with two eyes and a smile.

Protesters stood on its top to throw rocks, while teargas was shot from the other side, landing in front of the wall and hiding the grin between dancing clouds of stinging deterrent.

The simplicity of the painting and the speed with which it appeared say as much as the image. Smiles in the face of adversity.