Blake & Mortimer Vol. 18: The Oath of the Five Lords

The captain and the professor have finally made it to the secret base with the Swordfish blueprints, and construction has begun on the extraordinary machines. Olrik hasn't had his last word, though, and he is ready to take tremendous risks to locate the world's last bastion of resistance and freedom. A race against time is on between Imperial forces on one side and Mortimer's teams of engineers on the other... The fate of civilisation is at stake.