In 2202, an academic expedition detected tunnels of clearly unnatural origin beneath Maxwell Montes, the tallest mountain on Venus. Today, Professor Arthur Burgundy prepares for a follow-up expedition, and the team has been hired to provide security. Behind the scenes, shadowy corps muster their forces and prepare to control whatever the expedition unearths. Beneath it all, a slumbering evil stirs.

The Cytherean Malignancy features a heart-stopping action horror scenario for Shadows Over Sol. It is designed to run between one and three gaming sessions.