If you were captivated by the way The Sinful Ones blurs the boundaries between reality and illusion—where characters like Carr Mackay confront a world that reveals itself to be much stranger and more sinister than it appears—you’ll be enthralled by The City & the City. Miéville crafts a world where two cities occupy the same physical space, and the protagonist’s investigation forces him to question what is real and what is hidden. The psychological tension and sense of unreality echo the uncanny atmosphere that drew you into Leiber’s novel.

If you appreciated the morally ambiguous journey of Carr Mackay as he uncovers the dark truths behind his reality, you’ll find a similar thrill in The Demolished Man. Bester’s protagonist, Ben Reich, is driven by desperate motives and forced to navigate a society with intrusive psychic policing. The lines between villain and hero blur, and you’re left questioning whose side you’re truly on—a dynamic that echoes the ethical uncertainty at the heart of The Sinful Ones.

Drawn to the mind-bending twists and the surreal, almost dreamlike progression of The Sinful Ones? O'Brien’s The Third Policeman is a masterpiece of the unexpected, with a protagonist who stumbles through a bizarre, shifting world filled with strange policemen and metaphysical puzzles. Like Leiber’s work, this novel keeps you guessing about what’s real and what’s merely a reflection of the protagonist’s fractured perception.

If you enjoyed how The Sinful Ones delved into existential uncertainty—where nothing is quite as it seems and the very nature of reality is up for debate—Ubik will be right up your alley. Dick’s characters are haunted by shifting perceptions and metaphysical anxieties, and the story’s philosophical questions about life, death, and what lies between will resonate with your love of Leiber’s reality-bending themes.

If you were fascinated by the layered mysteries and hidden conspiracies that ensnare Carr Mackay in The Sinful Ones, you’ll relish the dense, enigmatic plot of The Crying of Lot 49. Oedipa Maas’s search for meaning takes her through a web of clues and secret societies, leaving her (and you) questioning the very fabric of her world. The novel’s labyrinthine structure and ambiguous revelations provide the same sense of intrigue and uncertainty.