As a WMG subpage, all spoilers are unmarked as per policy. You Have Been Warned.
The giant head in the flue is really Hugh Crain.
- Look at the picture of him in the picture with his second wife, Caroline.Then look at the flue head.
- When everyone examines the flue after Nell is first frightened by it, and later when it takes off Luke's head, it's quite clearly a lion. However, the lion's mane is very similar to Hugh Crain's hair, so it wouldn't be difficult at all for his spirit to "possess" and alter the flue's appearance to match his.
- Then there's the fact that Crain's ghost was originally supposed to come out of the fireplace.
