In 1900, a relief ship arrives at the remote Eilean Mòr lighthouse expecting to find three keepers waiting. Instead, the station is silent, the light is out, and there’s no sign of the men anywhere.

As the investigation unfolds, disturbing details emerge: damaged railings, missing equipment, and conflicting clues suggesting something sudden and violent may have happened on the island. But no bodies are ever found, and the official records don’t fully explain what occurred. It's almost like James Ducat, Thomas Marshall, and Donald McArthur had vanished into thin air.

For over a century, the world has wondered: Was it a freak "rogue wave" that swept them all away? Did one man snap and take the others with him? Or is there something even darker about the island the locals refused to share?