Just like its three predecessors, there is a lot of book inside. The location has shifted from East Anglia to the famously eerie Salisbury Plain, which is a grand setting for a ghost story. Series set in the same building can become claustrophobic and stale, so Ms Royal is canny enough to set this fourth book in another place. People’s troubles follow them, and Eleanor grapples with her feelings for Thomas, while he wrestles with a whole hellful of demons and a tricky secret mission. As with the other books, this is a very character-centered story and as much about the people and their lives and trials as the case, although that is very absorbing and is never allowed to take a back seat. Like all the best series, this one combines the dysfunctional characters and multiple plot strands with a sound underpinning of knowledge. I complained in my review of the last book that the plot wasn’t interesting enough, but now that has been remedied this is a series to be reckoned with.