July Books 4) Keys to the Kingdom (Locke & Key Vol 4), by Joe Hill
A problem with the Hugo category of Best Graphic Story is that the nominees are often very diverse in form. Here, for instance, we have the fourth of a six-volume sequence, itself consisting of six individual issues of which the first three are relatively distinct from each other and the last three more closely linked; but there is a lot of background knowledge for the new reader to pick up. I found the fourth in the sequence, involving a young boy and a ghostly soldier, particularly effective, and there is an excellent twist at the end. But there are some pretty gory moments as well, and the plot is necessarily incomplete. I don't think I'll look out for more of this series as a priority.
(I note that the author's father won a Hugo for non-fiction in 1982 but has never even been nominated in the fiction categories.)