Mike Flanagan is back to ruin your sleep this October. The director of Netflix hits like “Gerald’s Game” and “The Haunting of Hill House” has returned with his most ambitious piece to date, a textured mini-series that weaves multiple stories by Henry James into a tale of possession and how people can have a hold on someone in life or death. A deeply melancholic piece of work, “The Haunting of Bly Manor” drips not with ghostly ooze but loss and regret. It lacks some of the urgency of “Hill House” and will likely be deemed lesser simply by virtue of being nowhere near as scary, but there are a richness and patience to the filmmaking here that shouldn’t be dismissed simply because there’s no Bent-Neck Lady. Flanagan and his team of writers sometimes allow these characters to ramble on and repeat themselves in ways that can make the overall piece feel too talky, and the ensemble lacks when compared to the first one, but this is a complex, daring production in every other way.