Six episodes and it never once tries to be Arknights' big serious war story, which is exactly why it lands. Lungmen's back alleys get treated like a neighborhood instead of a battlefield: errands, petty disputes, the kind of nonsense case you'd hear over a pot of tea rather than a mission briefing. Lee holds the whole thing together as the unflappable center while Aak, Hung and Waai Fu bounce off him, four operators who normally live in supporting slots finally getting a room of their own. The ONA short format is the point, tight comedic beats with no room for padding, each case in and out before it wears out its welcome. That framing device, cases served alongside your tea, is the tell that this thing knows what it is. It's the side story where the city stops being a map and starts being somewhere people live.

In the shadowy back alleys of Lungmen City, a mysterious man named Lee shares his home with Aak, Hung and Waai Fu. Calling themselves Lee's Detective Agency, the four take on errands, look into mysteries and settle quarrels for the people who live around them. Across six episodes, the ONA presents a handful of their odd but genuine cases, mixing action with comedy as the crew works through each new job in their corner of the city.