Bone Keeper

A meteorite crashes into a remote woodland, depositing an alien creature that takes shelter in a cave system known as the Skirred caves in the Welsh wilderness. The creature survives across millennia, claiming victims from prehistoric times onward. In 1976, journalist James Wheeler enters the caves seeking the truth and is never seen again — only a single frame of Super 8 film survives, capturing the silhouette of something monstrous. Years later, Wheeler's daughter Lucy also vanishes while investigating the caves. In the present day, Lucy's daughter Olivia Wheeler gathers a group of friends — including biologists Nadia and Ravi, adventurers Ethan and Nick, her friend Annabelle, and a fame-hungry vlogger named Ashley — to mount an expedition into the Skirred caves to find her missing mother. Professor Harrison (John Rhys-Davies), who witnessed the creature in his own childhood and possesses found footage, warns them not to enter, but the group ignores him and descends into the depths. Inside the cave system, communication fails and the group discovers claw-marked walls, ancient slime, and traces of earlier explorers. Despite warnings, they split up. The enormous tentacular alien creature — the Bone Keeper — begins stalking and picking them off. The creature is oviparous and capable of dissolving and reassembling its prey into something unrecognizable. As terror escalates, the line between hunter and hunted blurs. The film builds to parallel endings showing different alien attempts to emerge from their subterranean environment, exploring themes of who the true indigenous inhabitants are — suggesting the alien predated humanity — and weaving in motifs of motherhood and maternal protection mirroring Olivia's search for Lucy.

Sources: IMDb, Heaven of Horror, Projected Figures, Variety, Prime Video, Letterboxd