It takes a great deal of careful plotting to make a good confined single location thriller. Films such as Buried (2010), The Pool (2018), and 4×4 (2019) rely on a variety of complications to maintain tension without becoming repetitive or overstaying their welcome. It’s a delicate balance, but when it’s done well, the results can be electrifying.

Writer Michitaka Okada adopts a unique conceit for their latest, #Manhole, which readily employs social media to drive the narrative of a successful realtor, Shunsuke Kawamura (Yûto Nakajima), who falls down an open manhole the night before his wedding.

Director Kazuyoshi Kumakiri cues audiences that phones will play a vital part by opening with an elaborate split-screen video of Shunsuke’s work colleagues taping congratulations at his wedding party. Immediately following the party, a drunken Shunsuke bids his friend Kase (Kento Nagayama) goodbye, stumbles down the street and almost immediately falls down a hole in the ground. Approximately 99% of the rest of the film follows his efforts to find his way out as he battles numerous obstacles, including a broken ladder, an infected leg injury, rising water levels due to rain, and a leaky gas pipe, all of which threatens his safety and/or plans to escape.

Unlike other films that disavow the use of technology or rely on conceits like no cell signal, dropped calls, or dying batteries, #Manhole leans into the idea that Shunsuke still has reception and can communicate with the outside world. Kumakiri uses familiar visual storytelling techniques to capture text on screen, or cuts to insert shots of Shunsuke’s phone screen as he scrolls through fictitious social media app ‘Pecker’ to galvanize his rescue efforts.

The way the film uses ‘Pecker’ is what helps to set #Manhole apart from other films in the subgenre. Shunsuke is savvy enough to realize that presenting as a young woman instead of himself is more likely to garner attention, so he creates a fake profile as his own (fictitious) sister under the handle ManholeGirl, then relies on chivalrous men to take up his cause.

Initially, Shunsuke believes the manhole is part of a construction site in Shibuya because that’s where the bar was, but between Community Affairs officers and the one individual he can reach, his ex-girlfriend Mai (Nao), he quickly realizes that his location is more of a mystery. The film becomes something of an investigation as a result: Shunsuke and the ‘Pecker’ community use freeze frames from video he takes on his phone, as well as the party, and from his photo roll to try and source his location.

The other novel element that Okada uses to make the film unique is that Shunsuke himself is more complicated than he initially seems. Early in the film Mai encourages him to call the police for help, but he shuts the idea down suspiciously fast. And when the internet begins to question if his fall was less of an accident, it’s revealed that between his 50-odd exes and the work colleagues that are jealous of his impending marriage to the CEO’s daughter, Shunsuke has more than a few enemies who might like to see him disappear.

These kinds of mini-mysteries, plus the usual physical threats, ensure that #Manhole remains entertaining and complicated throughout its nearly 100-minute runtime. By accepting the reality that modern technology, and particularly social media, can help, not hinder, the story when used properly, #Manhole manages to both surprise and entertain in equal measure.

The result is a pretty fun addition to the confined single location thriller subgenre.