Cheng Xin travels into space for the first time by space elevator, ascending from Earth to the old geosynchronous terminal station. The journey makes her recall Yun Tianming’s college thoughts about slow spaceflight, and in weightlessness she feels unexpectedly calm, as if she belongs in space. At the station, she passes through layers of human history preserved in its rings, from Great Ravine militarism to later urban normalcy.

At Port A225, Cheng Xin meets the PDC-and-fleet special team assigned to her encounter with Tianming. The fleet chief explains that the meeting will occur at the Earth-Sun Lagrangian point and will be monitored by the Trisolarans through Sophon. Three lights will indicate Trisolaran tolerance of the conversation, but a red light will trigger a miniature hydrogen bomb that will destroy Cheng Xin’s dinghy; if Cheng Xin dies, humanity will receive nothing.

Cheng Xin departs alone in the dinghy, aware that she may be seeing her last sunrise. At the Lagrangian point, an unfolded sophon becomes a communication screen, revealing Tianming on what appears to be a small farm aboard a Trisolaran vessel. Tianming looks young, healthy, and mature, and he tells Cheng Xin he has been farming with seeds she sent, while brief yellow-light warnings show that even indirect technical information is dangerous.

Through careful ambiguity, Cheng Xin confirms that Tianming has had access to sophon observations of Earth and that the farm’s light likely comes from the ship’s engine-related systems. Tianming says he has always been with Cheng Xin, meaning he watched her life from afar, but the Trisolarans prevent him from discussing his experiences directly. To avoid the restrictions, Tianming invents a shared childhood history and proposes telling old stories, signaling a safer method for passing information.

Tianming tells three connected fairy tales: The New Royal Painter, The Glutton’s Sea, and Prince Deep Water. Cheng Xin concentrates on memorizing every detail. When the meeting ends, Cheng Xin and Tianming promise to meet again at the star he gave her, their star; after a tense review period, the red light never appears, and Cheng Xin returns to the terminal station.

Back at the station, officials take Cheng Xin into a tiny sophon-free room, revealing that humanity can now create extremely limited blind zones from sophon surveillance. Cheng Xin records the conversation repeatedly, including under psychological guidance, so the special team can analyze Tianming’s hidden message. Later, as Cheng Xin breaks down in the space elevator, Sophon’s house on Earth burns, her robot avatar is destroyed, and she announces that all sophons in the Solar System will be withdrawn, possibly ending direct contact between humanity and Trisolaris.