Explanation:

A sequel to the Rouletabille Le fantome de l'Opera comic in which Rouletabille, Christine, and Erik embark on a very Tintin-esque adventure in Venice that involves a search for treasure, the dark arts, and ritualistic human sacrifice.

I have yet to scan images from this comic other than the three sequences below. The rest will be added soon.

Rouletabille rescues Erik after he has been imprisoned and tortured by the villians in Venice.

Christine and the Marquise about the be sacrificed by said Venetian villians.

Christine goes apesh*t after the Marquise is killed.