Eh, they introduce a new monster in this week's episodes, although if you've been paying attention it's not a big surprise. And apparently even Johan likes to recycle things over and over. I enjoy watching this, but when I think about it later things do seem pretty predictable.
Warning: Spoiler! to sum up the two episodes, Zuk is watched by a secret task force after so much corruption comes to light because of his relationship with the first cop to get killed. Grimmer and Zuk meet, go to the bank, listen to the tape. Grimmer almost loses it. Zuk goes home to find two cops waiting for him to question him. He lets them search and they find the candy and the muscle drug in his medicine cabinet, planted there by Johan. Then Johan shows up and shoots them, leaving the mess in Zuk's lap. Grimmer returns to again pass the cross-dressed Johan on the stairs. Meanwhile Tenma spends another night researching police files from 20+ years before. The cop who let him in shows him the morning's paper, which tells the story of Zuk, the promising and rising young police detective now suspected of murder, and how the three police leutenants were poisoned with a muscle relaxant in some candy - a story that is entirely too familiar for Tenma.
Grimmer and Zuk hide out in a place where Zuk played as a child, but the former secret police guys track him down and shoot Zuk several times via a sharpshooter in another building, purposely missing anything too vital. They want the tape. Tenma tracks down Zuk's mother and learns of the hiding place, but leaves before the mother, who is senile or perhaps an Alzheimer's victim, can begin reciting the story from the tape - they hid it with her - so he arrives just in time to stop the sharpshooter. But not in time for the monster in Grimmer to emerge and beat the hell out of the rest of the bad guys. Grimmer reveals that he, too, was a resident of 511 Kinderheim and subjected to the techniques that took place there, although he remembers little of it. Tenma patches up Zuk and they get him an ambulance to a hospital, Tenma patches up the others, and they leave to a motel to get Grimmer cleaned up. Their plan is to go rescue Zuk from the hospital before it's learned who he is and he's arrested.
IMHO based on what we hear on the tape, Johan's mother may have been abusive to him in some way, we already know he was trouble when he turned up at 511 Kinderheim, I am somewhat curious to find out what the story on that will turn out to be. Certainly as I noted earlier this can't be his first time posing as his sister, he's way too good at it.