Adventures of Superman 580 (July 2000) contains the second chapter of Critical Condition, in which Superboy, Supergirl and Steel enter Superman’s body to find and remove the kryptonite that is killing him, under the control of Emil Hamilton and the Atom. DeMatteis, Carlo Barberi and Juan Vlasco are the creative team.
The craft the heroes entered Superman’s body is gets destroyed, and Supergirl gets separated from Superboy and Steel. But all three continue with their task.
There is also a subplot with Deathstroke hunting down Encantadora. He does catch up with her in this issue, but she manages to escape him.
Towards the end of the issue, Steel enters the chamber where Sueprman is being kept, to the surprise of Hamilton and the Atom, who wonder who it is inside Superman’s body in the entropy armor.
The story continues in the next issue of Action.