Secrets by the Sea Drama: Cast, Story, Release Date & More

• Title: Secrets by the Sea
• Native Title: 海边的秘密
• Also Known As: Fa Yi Tong Yan, Gong Sheng, Hai Bian De Mi Mi, Who’s Lying, 共生, 法医童言
• Country: China
• Type: Drama
• Format: Standard Series
• Episodes: 30
• Airs: 2026 – ?
• Original Network: iQiyi
• Content Rating: Not Yet Rated
• Genre: Thriller
• Tags: Web Series, Suspense

Main Cast

• Zhou Dong Yu as Tong Yan / Shen Shao Jie — Main Role
• Peng Guan Ying as Lu Zhu — Main Role

Supporting Cast

• Wei Xiao Dong as Lu Jian Guo — Supporting Role
• Zhou Zi Xin as Liu Tao Tao — Supporting Role
• Huang Zhen Yu as Jiang Yi Zhou — Supporting Role

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Guest Cast

• Liang Jing as Yu Jing Hong — Guest Role
• Zhang Guang Bei as Zeng Da Nian — Guest Role
• Ning Wen Tong as Tong Gu — Guest Role
• Zhai Xiao Xing as Song Yao Cheng — Guest Role
• Patrick Zhang as Fan Da — Guest Role

Story

Set against the beautiful coastal backdrop of Haiya City in the autumn of 2011, Secrets by the Sea is a gripping Chinese thriller filled with hidden trauma, shocking crimes, and long-buried secrets. As the gentle coconut breeze blows and banana trees sway along the seaside streets, a dark mystery begins to unfold beneath the city’s peaceful appearance.

Lu Zhu, a skilled criminal police officer recently transferred from Beijing, arrives in Haiya City to begin a new chapter in his career. During an investigation involving a dispute over an injury assessment, he crosses paths with Tong Yan, a talented forensic doctor working in the same police branch. Their first meeting is far from pleasant, as their different opinions and professional approaches immediately put them at odds.

However, as they are forced to work together on difficult cases, Lu Zhu and Tong Yan gradually begin to understand each other. Their clashes turn into cooperation, and their cooperation slowly develops into trust. Behind Tong Yan’s calm and professional personality lies a deep pain that she has carried for years, while Lu Zhu also hides emotional wounds from his own past.

Just as their relationship begins to change, a horrifying rape and murder case shakes Haiya City. The disturbing details of the crime force Tong Yan to confront a nightmare she has spent most of her life trying to escape. Twenty-four years earlier, Tong Yan’s twin sister was brutally murdered by a serial killer, leaving behind a trauma that has never truly disappeared.

Now, the signs are impossible to ignore—the killer appears to have returned.

As the investigation deepens, Tong Yan realizes that the person responsible for her sister’s death may have been watching and following her for years. The new crimes seem connected to the tragedy that destroyed her childhood, pulling Tong Yan back into a terrifying past she believed was long buried.

Together, Lu Zhu and Tong Yan must race against time to uncover the truth before another victim falls prey to the killer. But the closer they get to the answers, the more dangerous the investigation becomes. In a city surrounded by the sea and filled with secrets, old wounds are reopened, hidden identities are exposed, and the truth may be more terrifying than anyone expected.

Secrets by the Sea promises an intense combination of crime, suspense, psychological mystery, and emotional drama, as two investigators confront both a ruthless criminal and the painful secrets hidden within their own lives.

Production

Secrets by the Sea is a Chinese thriller series set in the atmospheric coastal city of Haiya. The drama uses its seaside setting as an important part of its storytelling, contrasting the city’s peaceful tropical scenery with the dark and disturbing crimes taking place beneath the surface.

The series stars Zhou Dong Yu as forensic doctor Tong Yan / Shen Shao Jie, alongside Peng Guan Ying as criminal police officer Lu Zhu. The supporting cast includes Wei Xiao Dong, Zhou Zi Xin, and Huang Zhen Yu, while several experienced actors appear in important guest roles.

With a total of 30 episodes, the series is expected to explore a complex investigation involving a decades-old murder, a returning serial killer, and the emotional impact of unresolved trauma. The drama is scheduled to air on iQiyi and is currently listed as a 2026 release.

Trailer

The official trailer for Secrets by the Sea has the potential to introduce viewers to the drama’s chilling atmosphere and central mystery. Fans can expect glimpses of the coastal streets of Haiya City, tense crime investigations, forensic examinations, and the growing partnership between Lu Zhu and Tong Yan.

The trailer is also likely to tease the terrifying connection between a newly discovered murder case and Tong Yan’s tragic past. As disturbing memories of her twin sister’s death return, mysterious clues suggest that the serial killer responsible may have come back after more than two decades.

With suspenseful visuals, emotional flashbacks, and the question of who is truly hiding the truth, the trailer should give viewers an intriguing first look at the dangerous secrets waiting to be uncovered in Secrets by the Sea.