The date of the performance of this gripping scene in the dramas of Haymarket had been set by the Illinois Supreme Court in mid-September, and the theater was now carefully prepared. At the east end of the north corridor was the scaffold-stage, complete with a trap door. It had been used previously for other executions, disassembled, and stored in the basement of the jail. It was now put back together and adapted for the execution of these four men.

As pictured here, the scaffold was level with the balcony outside the cells on the upper level along the north corridor. Spies, Fischer, Engel, and Parsons faced west, with Illinois Street outside the wall to their right. Barely visible behind them is a large box in which the unknown hangman waited for his signal from the sheriff to sever with a chisel the rope that held up the trap. Accounts of the behavior of the doomed men differ in some details, but all accounts agree that they kept their composure, with Engel appearing almost exultant.

Below the anarchists, on benches, was the audience of witnesses. They numbered about 180 men, a little less than a third of them reporters. The rest included physicians, jail officials, and at least some members of the jury, whose presence was at the time customary, though not required by law. A few private citizens were admitted by some special connection. These witnesses could see through the window above the prisoners the silhouettes of police with rifles and ammunition belts on the roof of the adjoining wing of the jail. The manner in which the building was guarded, in reporter and eyewitness Charles Edward Russell's words, was "like a precarious outpost in a critical battle."

Once the prisoners were on the scaffold, their legs were pinioned and the nooses were put around their necks, the knot behind the left ear. This was done one man at a time, with excruciating deliberation. Then each man's head was covered with a large white hood that resembled a pillowcase, which was closed at the bottom with a drawstring. A portion of each man's neck was the only part of his body that was visible.

These "costumes" perhaps afforded them some measure of privacy, while also sparing the witnesses from observing too graphically the grotesque effects of hanging would have on their faces. The baggy white shrouds also served, as had trying them together, to diminish their individuality and humanity.

Sheriff Matson forbade gallows speeches, but he could not prevent each of the men from making one final outburst. Parsons, the last to speak, shouted out "Let the voice of the people be heard!" when Matson gave his signal to the executioner and silenced them all forever.