Strike is a Crime Detective series, with a Private Investigator (Strike) as the main character, along with Robin, who starts out as his secretary but becomes a partner in the detective agency about half way through. There are 7 books at the moment, soon to be 8 (September, I think, is the release date). The first 6 have been made into BBC series and are available on iPlayer.
They're very good, in my opinion. Better than Harry Potter. Although comparing a Crime Detective series to a Children's Fantasy series is a little hard to do.
Watch or read the first one and see what you think. If you like it even a bit, try the rest - they get better.