I pop the glass cage of the Giant brain as stated in the instructions found on top of it.
Then I teleport inside the cage and drop the 2 plastiques I found before.
Nothing happens but a female voice (not to sexy btw!) says some artifacts are going to mutate. My plastiques doesn't mutate and suddenly I'm teleported to a hangar roof in Yantar.
Even if I pick the PLastiques or not, the dialog with the Zombie nearby (Black Sea?) seem to be the proper one but... my doubt is:
Plastiques remain is its previous form or do they mutate to something different?
Nothing happens in the Brain chamber once i Dropped them and fearing to lose them I pick them up before being auto-teleporte to that Yantar roof.