My rating: a solid 4 stars
Smartly written with references you can "geek out" over (from Sir Isaac Newton who in this world, systematized the practice of magic as well as modern science to J.R.R. Tolkien), I enjoyed the book which has a bit of a "Dresden Files" flavour to it. I like stories about wizards in general, particularly ones with apprentice wizards who are learning their craft. The author is obviously familiar with London and I enjoyed both the historical and current-day references to that city. I had to look up some of the "London slang" used and I also pulled out a map a few times to get perspective on the geography but found that an enjoyable part of the read - I actually learned a few things. The world building is interesting with the weaving in of Gods and Goddesses creative and unique.
Set in present-day London, the story is about Peter Grant, a newly minted constable in the London Metropolitan Police who quickly learns, to his surprise, that he can see and speak with ghosts. This earns him a permanent assignment with the magical division of the Met and an apprenticeship with Detective Chief Inspector Thomas Nightingale.
If I have a criticism, it's about the pace. I found the story a bit meandering at times although as I'm writing this, I'm wondering if that was intentional - a character trait of Peter's mentioned many times in the book is his lack of focus and certainly as a reader, I felt the same at times.
I will definitely continue reading the series.