House of the Long Shadows (1983)

An ambitious American author accepts a $20,000 wager to produce a timeless novel akin to 'Wuthering Heights' within 24 hours. He heads to a secluded manor in Wales, only to find it inhabited by a peculiar assortment of characters. As he navigates the eerie atmosphere and the strange residents, he realizes that the manor holds dark secrets, complicating his writing challenge. Tension builds as the line between reality and fiction blurs, leading to an unexpected twist in his quest for literary success.