Set during the final days of WWI (and not to be confused with Overlord, which is set during WWII and comes out later this year), Trench 11 follows a small group of soldiers on a secret reconnaissance mission involving a deep underground Nazi bunker. The bunker turns out to be a seemingly abandoned facility, where German soldiers experimented on their own men--a failed experiment that they want buried before the Allies get their hands on it.
The experiment consists of some sort of parasitic worms that takes over the victim's frontal lobe (and look like thin spaghetti noodles), leaving them angry and with no sense of right or wrong, leading them to essentially turn on their own men. By the time the group discovers all this, they must find a way to escape the underground facility before the Germans blow it up, but not before the remaining victims of the experiment either infect or kill them off.
I've always been a fan of horror during this period and it's a shame that there aren't more films set during the World Wars or even during war in general. There's a lot of potential there that could breed some fairly solid genre material. Luckily Trench 11 is another example of that, as it delivers an interesting story along with some believable performances, especially from lead Rossif Sutherland as a shell-shocked Tunneler.
While there are some creepy-ish elements thanks to the movie primarily taking place underground and with little lighting, I wouldn't really consider it a scary film. It did have a nice gritty look to it that added to the realism the film offered. That's accompanied with some surprisingly gory, and at times, claustrophobic moments. It is, however, a bit of a slowburn movie as we learn more of the story as it naturally progresses. I can see the pacing being problematic for some viewers, especially if you don't buy into the story or its characters.
On the topic of the story--it isn't the most original, but the look and execution played out well enough that I'd consider it to be one of the better renditions from this particular "infected soldier" theme. Aside from the pacing, I had no real issues with the movie.