Colonel Colin Campbell, alias Dr. Richard Ames, alias Senator Richard Johnson, is enjoying an evening out with his date, Gwendolyn Novak, when a man approaches him in a crowded restaurant and tells him, “We need you to kill a man.” Colonel Campbell, a retired mercenary soldier who uses a cane (with a stiletto inside) because of his artificial leg, is about to brush the stranger off when the man adds, “Tolliver must die by noon Sunday or we’ll all be dead!” Before the uninvited guest can elaborate, or produce identification to substantiate his cryptic message, he is fatally wounded by a four-millimeter dart projected by an unknown assailant.
Certain that the assassin will be after Richard (as she calls him) next, Gwen offers him the use of her compartment as a temporary hideout. While staying with her, he discovers that the man who was murdered in the restaurant was one Enrico Schultz; yet when he attempts to investigate further, he is evicted from his living quarters and denied access to his terminal--a combination TV, telephone, and Automated Teller Machine. It seems that not only do those in power at the Golden Rule, the privately owned space habitat on which he and Gwen live, want to run them out, but both are wanted in connection with the murder of Schultz.
Ultimately, Richard learns who killed Schultz, the true identity of Tolliver, and why Richard is a threat to two opposing factions who want to seize Tolliver for their own purposes.
THE CAT WHO WALKED THROUGH WALLS is an entertaining, albeit long-winded, tale of technology and interpersonal relationships of the future. One can see ample evidence of Heinlein’s cleverness in his description of the scientific possibilities of tomorrow and the THIN MAN-style repartee between Richard and Gwen. Where this distinguished author of speculative fiction goes awry is in his plotting, which is top-heavy with climaxes and short on narrative development. Additionally, there is a plethora of characters running throughout the story, making it difficult to follow at times. For those who are interested, the cat of the title is a feline named Pixel, who is not introduced until page 318--to little or no effect.