Claude Opus 4.8 vs GLM 5.2 for book writing

The letters shouldn't exist.

They arrive addressed to Edith Brand's sister — dead for forty years — postmarked from a village that no longer exists, drowned beneath a reservoir since 1971.

Retired and haunted, Edith returns to the place she once called home, renting a room above the pub from a landlord whose memory runs deeper than the water. But the further she wades into the past, the murkier her sister's death becomes. Was it an accident? A tragedy of her own making? Or something darker, long buried?

Some secrets don't stay drowned.

And…

Retired lighthouse keeper Edith Brand thought the past was buried beneath the waves. But when letters arrive addressed to her dead sister—postmarked from their childhood village, drowned decades ago—she is pulled back to the shore. Returning to the ruins, Edith rents a room from a landlord who remembers far too much. As she delves into the murky depths of their shared history, she uncovers a chilling truth: her sister’s death forty years ago was no accident, and no suicide. What really happened the night the water rose? Some secrets refuse to s…