Empire of Passion was titled in its original Japanese In the Realm of Passion, a strong indication of how much Oshima grouped this film in with its controversial predecessor, the deeply affecting and sexually explicit In the Realm of the Senses. It's wholly unnecessary: Empire of Passion stands on its own, every bit as beautifully haunting as its predecessor - it might even be the superior film.
Oshima's twin masterpieces were bankrolled partially by French backers almost certainly because they were erotic thrillers, with an assumed emphasis on erotic. If Oshima had made Empire of Passion first, there's little doubt his bankers would not have let him make In the Realm of the Senses. Where the latter film flirted dangerously with twisted erotica for pornography's sake, Empire of Passion cannot be mistaken for anything but what it is - a horror film (with a touch of noir) in the Japanese ghost tradition that delivers themes of morality, guilt, and, yes, passion. If you looked up macabre in the dictionary, it wouldn't be too surprising to see a little mpeg of this film waiting for you.
Despite the film's gripping story, Oshima's visuals are the dominating force. This movie is fucking gorgeous. Shot by Yoshio Miyajima (who worked on much of Masaki Kobayashi's best work, including Harakiri), there is an eerie glow to everything here. Oshima uses backlighting and twilight impeccably - seriously, I want to rewatch the movie right now just thinking about it. It's a shame Criterion has only released In the Realm of the Senses on Blu-ray, as this is an equally worthy candidate for the higher-resolution format.
The big question (assuming you like silly artistic comparisons as much I do) would be which of the two films is better? I'm not surprised In the Realm of the Senses is the most famous Oshima film. It's clearly the more shocking and rebellious one. Likewise, Empire of Passion is more easily accessible. I don't know that I can think of more than a handful of people I'd feel comfortable recommending the earlier film to, while Empire of Passion would be well-received by a broader audience. Of course, I enjoyed the latter more, while I think In the Realm of the Senses is of more consequence. Ultimately, I'll just say I am happy to have seen both films and leave it at that. Oshima is one of the more iconoclastic filmmakers in the collection, and his twin masterpieces represent some of the most interesting viewing the collection has to offer.