BLAKE & MORTIMER - TOME 12 ATLANTIS MYSTERY

Deep under Sao Miguel island, rumoured to be the last
emerging part of Atlantis, Professor Mortimer has discovered
samples of a mysterious radioactive metal. Could it be the
Atlanteans' legendary orichalcum ? When he and his friend
Blake set out on an expedition into the depths to find out,
sabotage occurs at the hand of their old opponent Olrik. And
soon, all three will be embroiled in a power struggie far bigger
in scope than they could have imagined.