Deep Lurk 深潜 is an intriguing and immersive Republican era spy thriller; one of the few that pulled me in from start to finish. It is set in 1939, at the prelude to the first Battle of Changsha. Changsha was a strategic city that the Japanese tried and failed to take four times from 1939-1944. As a result, they were never able to consolidate their territories in Southern China. At the time, the Republic of China's Nationalist Army had seriously considered abandoning the city but Xue Yue, the commander in charge of Changsha's defense refused to budge. As a result of terrain, Changsha could only be flanked from the east or the west, making it a difficult city to both attack and defend. In this kind of set up, intelligence and counter-intelligence can make a win-or-lose situation difference for both sides.

After a botched assassination attempt on Xue Yue, a traitor escapes to Shanghai with strategic Changsha defense intelligence. Multiple parties converge upon him in Shanghai to intercept the intelligence. The players include both the Changsha and Shanghai station of the KMT Military Intelligence (NBIS), the Wang Puppet Regime, the Japanese Military and hidden CPC operatives. Yun Hongshen, the idealistic young second master of the illustrious Yun family is sent by his father Yun Muzhi to observe. Predictably, this sharp but impetuous young man raring to make a difference does more than that and his path tangles with that off brave young NBIS agent Wen Yeming tasked to hunt down the traitor. An auction for stolen intelligence relating to the Japanese army's plan of attack for Changsha results in a deadly scramble to obtain or retrieve the intelligence. This coincides with the re-emergence of Kunwu, a long dormant Japanese spy and Muzhi's nemesis. Hongshen is lured back to Changsha, where he must crack the code to the intelligence and smoke out Kunwu in order to save his city from the encircling Japanese army. He reunites with Yeming at NBIS where they pit their wits against this master spy who seems to be able to see all without being seen.

The first three episodes are fast paced, exciting and littered with clues and character introductions and needs to be watched (and re-watched) carefully. But the setup and the storytelling is so intriguing I was compelled to re-watch; to make sure I didn't miss anything. It's been a long time since a drama pulled me in so deeply that I was literally unable to watch anything else at the same time. Even though there are some logic holes, the overall plot is tight and riveting. All the important characters are introduced early on and they are multi-faceted and grey with different loyalties and motives that reflect the clash of culture and ideology and the rival factions within the KMT during that pivotal era of change. The narrative brilliantly builds a credible case around several key characters with motive, means and opportunity to be Kunwu and maintains the suspense into the final episodes.

This drama has an all-round stellar cast anchored which by veteran actors including Wang Jingsong and Liu Huan and brilliant character acting by Hou Mengyao's disingenuous Milan, Han Chengyu's ruthless and competitive Ling Han and Zhang Tianyang's well-meaning Yun Hongqi. I really enjoyed watching Hongshen meticulously narrow down the suspect list and try to out-scheme the hidden master spy who eluded his father for years. The young Cheng Yi brilliantly captures how this character's intelligence and survival instinct makes up for his lack of experience and the shattering consequential mistakes he makes along the way. It is a shame that this drama has not enjoyed wider viewership. For this genre however, I don't need romance and I didn't enjoy Ying'er's acting or the couple's chemistry. I was far more invested in the Yun family's close bond and amused by how Hongqi and Hongshen are so different and resourceful in their own unique ways. Zhang Tianyang is a subtly hilarious actor and his brotherly scenes with Cheng Yi are among the drama's best moments for me.

Despite many cut scenes, the pacing, suspense and excitement holds up into a strong finale that delivers a good ending twist that deftly avoids one reversal too many. My only disappointment is that I had hoped for a more complex villain origin story. I won't say more to avoid spoiling the reveal. This is by far the best Republican spy drama I have watched since The Rebel (2021). I am happy to rate it the same at 8.5/10.0 despite its lower budget. It is a good watch if you are in the mood for some mental gymnastics but it can also be enjoyed simply as a fast paced spy thriller.