For the first time, the tide stops.
MAREA ROJA (Red Tide) Logline: In a forgotten coastal village where the sea has turned blood red and silence falls at dusk, a skeptical marine biologist discovers that the toxic algae bloom is not a natural disaster—but a sentient reckoning for the town’s buried sins.
DR. VALERIA SOTO (30s, sharp, haunted by a past failure in her field) arrives on Isla Santa Marea after being summoned by her estranged aunt, a local elder. The town’s fishing industry has collapsed. The “marea roja” – a red tide of toxic algae – has returned for the third straight year, but unlike any she’s seen. It glows faintly at night. It moves against the current.
Valeria learns that the original 1978 sinking of the Santa Marea – a smuggling vessel carrying migrant workers – was ruled an accident. But Elena reveals a mass grave in the mangrove swamp: skeletons fused to mangrove roots, their mouths sealed with hardened algae.
Valeria meets young fisherman DIEGO (20s, curious, unafraid) and his abuela, ELENA (70s, fierce, keeper of old stories). Elena warns: “The red tide is not a bloom. It is a memory. A long time ago, the town let a ship sink. They left people inside to drown. The sea has not forgotten their screams.”
Ecological Thriller / Slow-Burn Horror Setting: Isla Santa Marea, a remote fishing village on the Pacific coast of Mexico. Worn wooden docks, salt-cracked concrete, a shuttered cannery, and a lighthouse that no longer works. SYNOPSIS ACT I – THE TURNING