Novel: The Cat Who Walks Through Walls

Overview

The Cat Who Walks Through Walls is a rollicking blend of mystery, science fiction, romance, and metafiction that reunites many characters and ideas from Robert A. Heinlein's later fiction. It opens with a chance meeting between a pragmatic, world-weary narrator and an alluring, enigmatic woman, and quickly pivots into a murder, a chase, and a conspiracy that spans planets and realities. A small, uncanny cat that literally walks through walls becomes both a literal plot device and a symbol of the porous boundaries between worlds.
Heinlein threads action and banter with philosophical digressions, shifting tone from hard-edged adventure to affectionate pastiche of his own career. The novel uses a lean, conversational first-person voice that mixes technical savvy, wry humor, and affectionate nostalgia for recurring characters drawn from Heinlein's "future history" and "World as Myth" ideas.

Main characters and relationships

The narrator is a competent, practical man whose life is upended when he meets a woman who introduces herself as both irresistible and dangerous. She recruits him into a scheme that rapidly escalates into murder and exile. Their relationship, equal parts partnership, flirtation, and shared danger, drives much of the book's emotional core.
Pixel, the cat who can pass through solid matter, is a memorable and oddly philosophical companion whose behavior underscores the novel's play with impossibility. Lazarus Long, Heinlein's long-lived antihero, appears and connects this story to a wider tapestry of characters and timelines, reinforcing themes of longevity, freedom, and personal choice. A rotating cast of cameos and returning figures ties the adventure into Heinlein's broader mythos.

Plot arc

A quick, almost casual beginning, an encounter in a social setting, turns into a framed murder and a violent political tangle. The protagonists are forced to flee and improvise, moving from one improbable escape to the next. What starts as a noirish caper becomes an interstellar odyssey that explores alternate universes and the practical consequences of immortality and myth made real.
The stakes grow as personal loyalties clash with ideological battles. Revelations about motives and identities unfold amid chases, skirmishes, and maneuvers that are clever more than spectacular. The climax stitches together personal resolution and speculative exposition, leaving characters reconfigured by shared experience and by the book's metaphysical conceits.

Themes and style

Heinlein delights in mixing genres: detective elements, space opera, philosophical dialogue, and self-referential humor. Central themes include personal liberty, the ethics of intervention, the burdens and liberties of long life, and the nature of reality when fiction and fact intertwine. The novel celebrates resourcefulness and independence while interrogating the costs of living by one's own rules.
Stylistically, the prose is brisk, talky, and plainspoken, full of asides, technical detail, and character-driven banter. Fans of Heinlein will recognize his recurring moral certainties and his fondness for larger-than-life individuals who forge their own destinies. The result is an energetic, sometimes uneven, but always engaging ride that functions as both a standalone adventure and a capstone of recurring motifs in Heinlein's late work.