That Hideous Strength

 is a Sunless Skies Random Event.

Story description
Tensions are high, and the crew are making mistakes.

''The preternaturally fertile seeds of the Reach must be stored with the utmost care. A flicker of light, a lap of moisture – and they burst into violent growth.''

Like the sack in your hold, from which questing vines have groped, knotting around your cargo.

Trigger conditions
Terror ≥ 50 ≤ 79, Sack of Verdant Seeds ≥ 1 Location: The High Wilderness Area: The Sky Frequency: High Terror (100%)