The plot of the book is significantly different from the film, but features many of the same characters. Eddie Valiant is a hard-boiled private eye who lives in a strange universe in which humans and "toons" co-exist. Roger Rabbit, a popular toon comic strip star (in this world comic strips are made by "photographing" toons in action) is one day mysteriously murdered in his lavish Hollywood home. His speech balloon, found on the crime scene, seemed to indicate his murder was a way of "censoring" the star, who apparently had just heard someone explain the source of his success.
Valiant's search for the killer takes him to a variety of suspects including Roger's widow, Jessica Rabbit and his former co-star Baby Herman. The book has a surprise ending.
Another Roger Rabbit book entitled Who P-P-P Plugged Roger Rabbit?: A Hare-Raising Mystery was also written by Wolf. The book was a sequel to the film and not the first book however, so Roger is still alive in it.