To me, Vincent Price has always been one of those rare actors whose movies you watch simply to see his performance. Whether or not the movie has any type of an interesting plot is entirely a secondary concern. Price rarely does a poor performance, and if the movie itself ends up being entirely terrible, you can count on him at least to give a momentary relief from the pain of having to withstand an awful movie. As for Diary of a Madman, I’m a bit all over the place with this one. As a movie, it’s not particularly great. It’s very silly, dated and despite being framed like a slow burning thriller, it’s very uneventful, even boring at times. That’s why it’s a good thing Vincent Price has such a dominating role in it as the central protagonist whose story you are told via an extensive flashback after his untimely death and funeral at the beginning of the movie. Even when the story at times isn’t that particularly compelling, you’re very much engaged by Price’s solid performance as a man who starts to doubt his own sanity and later on anguished by guilt and horror when a murder take place.
For a 60s horror movie it has surprising amount of subtlety and intrigue as a sort of proto-psychological thriller that later proved to be a rather popular genre. The initial set up where Price wasn’t sure if he was losing his mind or not was quite riveting. The mundane way they built up Price’s own self-doubt via objects having moved without explanation and Price seeing things that weren’t there was a very effective and natural way to show how the seeds of suspicion were planted to his mind without coming off too hammy. They honestly could have done more with it but given the confines of the running time, it was understandable that they had to move on with the story relatively quickly and establish Horla, the spectre that posses people and makes them commit horrible acts for its own perverse amusement, as being real so that they could start building up the conflict of Price trying to maintain control of his body that led to Price’s death in the end. The possession effects were unfortunately incredibly dated by today’s standards. They couldn’t make Price’s eyes glow when he was moving due to the limitations of the technology, so they could basically only show the effect when the possession was starting and Price’s face is conveniently kept perfectly still. But somehow the movie still ended up with one shot where the glow doesn’t align right with the eyes, and is instead a bit off, which was a bit amusing to me. It’s just so odd how they decided to leave it like that. Maybe they just didn’t have the money to fix it.
The first half of the movie is relatively okay, but doesn’t offer much in the form of a compelling narrative hook. This is for the most part due to the opening act failing to lay out an interesting mystery behind the death of Price’s character. They talk about it a lot in the funeral, but they don’t manage to make it be mysterious enough to make you invested i the story from the very beginning. It’s too sterile and the movie more or less just assumes you will be interested, rather than provide you with a seductive tease of what’s to come. That’s why it’s only in the second half, after Horla has made his presence known, where things finally start to come together. Price, still unwilling to believe the supernatural exists, instead decides to consult a physician who encourages him to pick up sculpting again as a way to break free from his routines and provide relief that would cure his ill mind. This leads us to the actual meat of the story, the tragic love affair between Price and his future sculpting model, whose subsequent murder really amps up the excitement in the story when Price realizes what Horla made him do. I’m not usually a fan of shallow romance subplots like this, but Nancy Kovack is absolutely charming and she has great chemistry with Price which is why the abruptness of her leaving her painter husband for Price after Price wants to marry her only then to just immediately get killed isn’t as clunky and jarring as one might expect.