A very good horror about doctors - experimenters who want to resurrect people. Intentional or not, but in addition to the "Thirteenth" from House in the title role, here and the head doctor at the hospital made look like Cuddy.
In terms of horror, it was good to create an oppressive atmosphere of anticipation of something bad. Scrimmers are placed competently and make you strain even more.
The plot is also extremely good and the holes are not full (unless the guard has disappeared somewhere). You could say we didn't have pianos. A sharp turn at the end could also fit.
Good horror, worthy of attention.