Exeter, London, Tiverton, and Salisbury, England
One of the hazards of being hunted by magicians is that you have to be on the move a lot. Therefore, the Ryves Bros. & Co. do quite a bit of traveling in this story, which gives us quick peeks at quite a few UK sites, including Gothic cathedrals and ancient battlegrounds, old pubs and close-packed houses with slate roofs. What's the biggest thing we get from all of these little peeks? A sense of the historical weight of the area and the potential for ancient tales, folklore, mystery, and magic to be hidden behind every spire and balustrade.
The book begins with Nick and Alan in Exeter, but when ravens invade their kitchen (meaning that the magicians have found them once again), it's time to relocate. Nick suggests London because he knows Alan will enjoy being near all of the museums, so they head northeast, and that's where the bulk of the rest of our story takes place.
There are side trips to Salisbury, where Nick and Jamie are dropped outside Salisbury Cathedral to explore the town and seek out magicians, and though we don't get the details, Mae and Alan take a quick trip to check out Stonehenge. There's also a quick detour to the Isle of Wight, where we encounter yet another residence that could easily be the setting for a Gothic film. (Incidentally, in our minds The House of Mezentius looks a lot like the real life Isle of Wight estate Appuldurcombe House.)
Put all of these pieces together, including the final scenes which take place in an expansive row house off of Royal Avenue (a rowhouse we imagine may resemble one of these), and you have the perfect setting for this modern Gothic novel.