[1][2] The story focuses on a personified cat named Fritti Tailchaser, set in a world of other anthropomorphic animals who live in their natural environments but each have their own language, mythology, and culture.

Tailchaser's Song begins, after quoting a poem by Christopher Smart, with an exposition of the central elements of the cats' mythology, starting with a creation myth.

Meerclar Allmother is identified as the primordial creator of all other beings, who brought forth a pair of cats who are the progenitors of the entire species as well as divine figures.

Together, they set out on a long journey to visit the feline royal Court of Harar, with the intention of resolving the mystery of the disappearances.

They are captured by a group of evil cats called the Clawguard, and taken to Vastnir, an enormous mound far to the north, where the evil cat-god Grizraz Hearteater enslaves cats to take over the world, swollen in size and sitting upon a mound of dead and dying creatures.

Soon, Roofshadow creates a hole from above ground, and Tailchaser manages to escape, and races to Ratleaf Forest, where he asks a clan of squirrels to alert them for him in repayment for a debt contracted with their lord's brother.

Lord Hearteater creates the Fikos, a dog-like monster of terrible power, out of the mound of dying creatures he had been sitting on.

Pouncequick, after healing from the loss of his tail, decides to return to Firsthome, the seat of the court, and stay there.

Firefoot appears to him in a dream, confirms that Hearteater's power is broken, and encourages Tailchaser to continue his quest for Hushpad.

The ending may be seen only as the beginning of a longer saga, but, to date, Tad Williams has yet to revisit his feline homage to Tolkien with additional writings.

The novel contains a developed system of cat speech and style as well, to go with their customs; it is very similar to what the reader finds in written editions of the works of J. R. R. Tolkien.

Tad Williams has come up with a very large variety of terms, called the Higher Singing, used by the cats to express themselves and explain things.

In November 2011, it was announced that Animetropolis is developing a computer-animated film adaptation, with International Digital Artists, the producer of Cat Shit One, animating it.