"The Cat Who..."  Books
By Lilian Jackson Braun
1.  The Cat Who Could Read Backwards

2.  The Cat Who Ate Danish Modern

3.  The Cat Who Turned On and Off

4.  The Cat Who Saw Red

5.  The Cat Who Played Brahms

6.  The Cat Who Played Post Office

7.  The Cat Who Knew Shakespeare

8.  The Cat Who Sniffed Glue

9.  The Cat Who Went Underground

10.  The Cat Who Talked to Ghosts

11.  The Cat Who Lived High

12.  The Cat Who Knew a Cardinal

13.  The Cat Who Moved a Mountain

14.  The Cat Who Wasn't There

15.  The Cat Who Went Into the Closet

16.  The Cat Who Came to Breakfast

17.  The Cat Who Blew the Whistle

18.  The Cat Who Said Cheese

19.  The Cat Who Tailed a Theif

20.  The Cat Who Sang for the Birds

21.  The Cat Who Saw Stars

22.  The Cat Who Robbed a Bank

23.  The Cat Who Smelled a Rat

24.  The Cat Who Went up Creek

25.  The Cat Who Brought Down the House
Also (not a part of the series):

The Cat Who Had 14 Tales