New York Times bestseller Spencer Quinn returns with a laugh-out-loud series about the most epic rivalry of our time . . . Arthur the dog vs. Queenie the cat.

From the outside, Queenie the cat and Arthur the dog appear to have a lot in common. Both pets live in the charming Blackberry Hill inn. They both love their humans, twins Harmony and Bro. They both have a fondness for sausage. But that doesn't change the fact that they are mortal enemies. Goofy, big-hearted Arthur loves everyone he's ever met . . . except the snobby, scheming cat who's devoted her life to ruining his. Queenie is a bit choosier. And who can blame her? When you're brilliant AND exquisitely beautiful, you can't be expected to rub tails with commoners. Especially not slobbery dogs. But when the twins' beloved cousin is framed for murder, Queenie and Arthur must work together to clear his name . . . something Queenie finds even more distasteful than inexpensive caviar. Can two enemies put aside their differences long enough to solve the mystery?