Jennifer Connelly, Mike O'Malley and Daveed Diggs in 'Snowpiercer.'
CNN  — 

Seemingly a difficult concept in the best of times, “Snowpiercer” becomes more problematic in the midst of a pandemic, focusing as it does on humanity’s warring remnants in a post-apocalyptic world. Even adopting a charitable view of that bleak outlook, the show suffers from soapy silliness, stilted situations and a lack of narrative momentum, preventing this train from ever getting out of the station.

TNT moved up the heavily promoted premiere a few weeks, and the network is surely enthusiastic about having a show with ties to Bong Joon Ho, the Oscar-winning director of “Parasite,” who made his English-language debut on the 2013 movie.

Still, the premise about “a great ark train” – 1,001 cars long – ferrying survivors around an ice-covered Earth chokes on dense plotting and a mostly nondescript collection of characters.

In the late 1970s, NBC launched a notoriously expensive dud titled “Supertrain,” so students of TV history likely saw this as a derailment waiting to happen.

Based on a French graphic novel, the series is all about class inequality, with the train providing a heavy-handed way of exploring the social pecking order. Seven years into this sobering reality, the poor live in cramped, horrible conditions in the train’s tail, with ascending levels of privilege and luxury as you travel up the cars to first class.

As if building that rolling world weren’t enough, “Snowpiercer” sets its plot in motion with the oldest of devices – namely, a murder mystery. Specifically, someone has been gruesomely killed in one of the front cars, prompting the train’s officious bureaucrat, Melanie Cavill (Jennifer Connelly), to recruit Andre Layton (“Hamilton’s” Daveed Diggs), a one-time detective living in the tail, to come forward to solve the case.

If that sounds kind of ridiculous, wait, there’s more. Layton reasons that gaining access to the front will provide crucial information that will help the tail dwellers mount a rebellion. The investigation enables him to glimpse the first-class zone, including gladiator-style fights for the right to earn an upgrade, as well as secrets about the management of a conveyance that can “never stop.”

“Snowpiercer” certainly has plenty of social commentary woven into its concept. In addition to a nightmare vision of climate change, the class tensions are exacerbated by the fact everyone is trapped in close quarters – a reasonably good if inadvertent metaphor, as it turns out, for the world’s current predicament.

Still, it’s a big idea poorly done, and too heavy-handed in its approach to resonate much on that level. What remains is a whole lot of violence (which includes using the frigid weather outside as a grisly form of punishment), a little sex, and uninspired relationships involving the thinly drawn characters in its sprawling cast.

TNT has already renewed the series for a second season, so don’t expect closure when this 10-episode run ends. Yet while the train’s journey across that frozen wasteland might not be able to stop, viewers who start down this disappointing track don’t face any such restrictions.

“Snowpiercer” premieres May 17 at 9 p.m. on TNT, which, like CNN, is a unit of WarnerMedia.