The Cat Who... is a series of twenty-nine mystery novels and three related collections by Lilian Jackson Braun and published by G. P. Putnam's Sons, featuring a reporter named Jim Qwilleran and his Siamese cats, Kao K'o-Kung and Yum Yum. The first was written in 1966, with two more following in 1967 and 1968. The fourth appeared eighteen years later, after which at least one new novel was published every year until 2007. A thirtieth novel, originally announced for 2008, was postponed indefinitely by its publisher and then canceled after the author's death in 2011. It remains unpublished.