If you were fascinated by the speculative biology and hard-science approach of the Pak in Protector, you'll be captivated by Blindsight. Peter Watts crafts a gripping first contact scenario where alien life and consciousness are explored with rigorous scientific detail. The novel delves deep into neuroscience and evolutionary theory, challenging your assumptions as it unfolds.

If you loved the way Protector immersed you in the unique biology and motivations of the Pak, The Mote in God's Eye will enthrall you with its deeply realized alien civilization—the Moties. Their complex society, biology, and psychology are unraveled through tense human-alien interactions, making for a thought-provoking and immersive read.

If you were drawn to the way Protector plays out across vast spans of time and space, Tau Zero is a perfect match. Anderson's novel follows the crew of the Leonora Christine as they hurtle toward the end of the universe, delivering breathtaking scale and a sweeping narrative that grapples with cosmic stakes and human perseverance.

If you appreciated the evolutionary and existential themes in Protector, Childhood's End will resonate with you. Clarke crafts a profound story about humanity's transformation under the guidance of enigmatic aliens, raising questions about the nature of intelligence, destiny, and what it means to be human.

If you enjoyed how Protector balanced personal stories with grand SF ideas, you'll love Gateway. Pohl masterfully weaves the enigmatic Heechee artifacts, the mystery of space exploration, and Robinette Broadhead's psychological journey into a complex, layered narrative that keeps you guessing until the end.