Once everyone leaves the cell, Edmond heads over to look at Faria's sack-covered body.
After despairing and contemplating suicide, he suddenly gets a brilliant idea.
Using Faria's tools, he cuts a whole in the sack and removes Faria's body. After putting the body in his own bed and covering it in bedsheets, he gets into the sack and sews himself inside.
He has a plan of attack all thought out:
If the guards figure out he, a living man, is inside the bag, he'll cut it open with the knife, scare them, then run.
If they bury him, he'll wait for a suitable moment to dig himself out of the grave – which will no doubt be shallow – then run.
If he can't get out of the grave, then so be it. He was probably going to end up dying anyway.
After suffering the whole night through, Edmond finally hears the guards enter. He gets confused when he hears them discussing "the knot."
The guards carry him a short while, then stop. A moment later, he feels a rope being tied around his feet. Now the guards are discussing the roughness of the sea; one remarks, "Yes, the abbé runs a serious risk of getting wet" (20.44).
Edmond is confused. Suddenly, he can feel the guards swinging him, and then he's falling, flying through the air. He cries out the moment he hits the water. He's being dragged to the bottom of the sea by the thirty-six pound cannonball attached to his legs.