It consists primarily of: 1) a voice-over reading from Lovecraft's letters and stories, with photos and illustrations of him, his family and friends, and buildings and locations that were important in his life. Sometimes short clips of video of some of the buildings and locations as they appear today are shown. 2) interviews with Ramsey Campbell, Neil Gaiman, S.T. Joshi, and Brian Lumley. These are all well-spoken, informed, and even funny men who have a lot to say about Lovecraft and his work, and their interviews were the most interesting and entertaining part of the documentary for me.
There are a lot of other things in the documentary as well. There are shorter interviews with other people, such as filmmakers who have adapted Lovecraft's work. Some or all of that footage was taken at one of the annual Lovecraft Film Festivals in Seattle, Washington. Some musical acts that have been influenced by Lovecraft are quickly covered by displaying album cover art, and part of a performance by the band The Darkest of the Hillside Thickets at the Film Festival is shown. There are also interviews with people who play the role playing game Call of Cthulhu (interviews with the creators of the game would have been nice), and live- action role players from the H.P. Lovecraft Historical Society.
Parts of the documentary that I did not so much care for were: black and white clips of a supposed Professor at Lovecraft's fictional Miskatonic University, and a short segment of about six minutes consisting of a "Blair Witch" type drama of filmmakers going to investigate a "real-life" cult that worships the gods from Lovecraft's story. I thought it would have been better without these. There are also clips of an actor portraying Abdul Alhazred, the Necronomicon's author, but those I didn't mind as much.