‘When The Stars Gossip’: Is Ryong hiding a secret that could change everything between him and Eve?

Spoiler note: This article discusses plot developments through Episode 12 of When The Stars Gossip, which aired February 9, 2025 on tvN.

Yes, Gong Ryong (Lee Min-ho) is hiding something specific and consequential. By the end of Episode 12 of the tvN series, the drama has established exactly what that secret is: an unauthorized human embryo fertilization experiment conducted aboard the LEO space station, carried out alongside Kang Kang-su (Oh Jung-se), the veteran space experiment expert who had been in orbit for ten months. The remaining question entering Episodes 13 and 14 is not whether the secret exists but what breaking it open will cost everyone involved, including Commander Eve Kim (Gong Hyo-jin).

Why Ryong Really Went to Space

The experiment predates Ryong’s feelings for Eve entirely. He did not travel to the station because of the romance. He went to perform intracytoplasmic sperm injection (ICSI) in zero-gravity conditions for his patient Na Min-jung (Baek Eun-hye), who wanted to conceive a child using her late husband Choi Dong-hun’s sperm. If the procedure had worked without interference, it would have represented the first time human egg cells were taken to a space station for fertilization.

Ryong smuggled Na Min-jung’s eggs aboard the station and worked with Kang-su to develop the embryos, which reached the morula stage, an early-stage embryo roughly three to five days after fertilization. Framing the secret as something Ryong did because of Eve misreads the timeline the show established over its first several episodes.

What Eve Already Destroyed

The morulas from that initial experiment did not quietly survive to Episode 12. What the investigation uncovers in Episode 12 is not those originals but a subsequent embryo.

The unauthorized incubator housing that secondary embryo is the physical evidence at the center of the investigation. This distinction matters because it means the investigation reveals something Ryong actively reconstituted after Eve had already intervened once.

What the Footage Actually Shows

The Episode 12 confrontation was set off by Kang Tae-hee (Lee El), IOU Space Center vice president, who was reviewing security footage from the station. In the background of one clip showing Eve and Ryong together, she spotted the incubator. Cross-referencing the station logs confirmed that the device had been drawing power continuously through the period when the debris strike forced all other systems to shut down. Han Si-won (Lee Hyun-kyun), the director of flight operations, was also part of the footage review.

The detail is damaging because an incubator maintaining temperature through a station emergency is not something that happens by accident. That decision left a logged record. By the episode’s end, Tae-hee has called both Ryong and Kang-su in and placed the evidence in front of them.

Kang-su’s Position in the Investigation

Kang-su’s cooperation with the investigation is not guaranteed. A full account of the morula experiment requires explaining his own participation. He is the qualified scientist who had been on board for ten months with access to the experiment hardware, and any testimony implicating Ryong would also implicate him.

There is a second factor. The secondary embryo in the incubator has not been implanted in Na Min-jung. If Kang-su’s testimony brings it under regulatory scrutiny, its fate becomes uncertain, directly affecting the outcome Na Min-jung has been waiting for. He is not loyal to Ryong, but the downstream effects of full disclosure touch people beyond either of them.

That calculation has a limit. If Tae-hee’s investigation creates enough institutional pressure, Kang-su’s interest in limiting his own exposure becomes the dominant variable.

What Full Exposure Would Cost the Crew

The show frames conducting an unauthorized human embryo experiment without regulatory approval and in violation of international space protocols as a criminal matter, not a procedural one. Based on what unfolds in the episodes that follow, international space authority involvement means potential termination for the entire crew. Eve held command responsibility for the mission, and her documented non-involvement does not automatically insulate her from institutional consequences.

The morula storyline also involves the interests of the Choi family and the MZ Group, who had a stake in Na Min-jung’s situation. That dimension runs well beyond what any one person on or off the station can manage quietly. If the investigation reaches that level, the fallout will not be contained to Ryong and Kang-su.

The Separate Thread About Eve’s Background

Running alongside the incubator investigation is a distinct storyline about Eve’s family history. The show has established, through earlier flashbacks, that Eve was found as an infant with no record of her biological parents seeking her. A woman in Ryong’s personal life, Jung Na-mi, has been positioned in the narrative as a figure connected to Eve’s past, though the explicit link between them has not been confirmed on screen as of Episode 12.

These two threads have not converged, and Tae-hee’s investigation has not touched this storyline. What they share is that both involve facts Ryong does not currently know, facts that would reshape his closest relationships once they emerge.

How the Experiment Changes the Frame

The covert mission changes the interpretive frame for everything that followed between Ryong and Eve. He was not a tourist who fell into an unexpected situation. He arrived with a concealed plan that violated protocols Eve was responsible for enforcing, and he continued that plan after Eve had already intervened once. Whatever happened between them developed alongside something she did not know about.

That does not resolve his exposure. But it does affect how her eventual response to the full picture reads. Eve is not a character who treats procedural breaches as negotiable. What she does when she learns the scope of what Ryong did, and why he did it, is a more precise question than whether he was simply impulsive. The incubator was running quietly in the background of footage that was being reviewed for something else entirely.