Liza, along with her son Jude and husband Sean, moves to the Heelshire Mansion in the English countryside to recover from a traumatic home invasion. While exploring the grounds, Jude discovers a lifelike porcelain doll buried in the forest. He names the doll Brahms and quickly forms an unnaturally strong attachment to it. This bond concerns Liza, especially as Jude begins communicating through the doll and exhibiting disturbing behavior. Strange occurrences around the house escalate as Brahms’ influence over Jude deepens.

Liza's attempts to separate Jude from Brahms are met with increasing resistance and inexplicable events. The family learns of the dark history surrounding the mansion and the doll from local sources, who warn them of the malevolent force they have unwittingly invited into their lives. As Liza delves deeper into the mystery, she faces a race against time to save her son from Brahms’ sinister control, while confronting the emotional scars that their family tragedy continues to inflict upon them.