As the party stands together sorting out their mind-sets and considering what's just gone on in the last hour, with the house well in sight, they piece together bit by bit the realization that knowledge of the gem will not simply let them go. There is a clear understanding that they have not been able to keep themselves from thinking about the gem since arriving. During their conversation, they find themselves continuously talking about the gem. With a great clarity, they feel a foreknowledge that sleep will be impossible without possessing the gem. They must have it. They cannot leave this place until they do.
While that prospect is frightening, it remains the fact of the matter. They may be able to resist for a time, but sooner or later they will have to go get the thing ... no matter what consequences that brings. Each member of the party understands this. Each member cannot change it.
Devereaux's house stands there. The weather is unchanged. Only now the overcast conditions seem dreadful and foreboding. The moderate breeze that felt good on the ride up now seems to sting the skin with bits of sand, threatening to drive a man mad. The temperature that was pleasant before now seems thick and cloying in the player's throats.
All about seems hateful and ugly. And each companion looks at one another with doubt, irritation and fear.