Think of "Keep the Lights On" as a companion piece to last year's wondrous little film "Weekend" (which was on my Top 10 list of 2011). Gay men, who have played a major role in creating and developing cinema, are FINALLY turning their cinematic attention to gay relationships. It only took 100 years. And we're not talking about superficial melodrama or soft-core porn. There's no beefcake in either one of these films. These are also not coming-out stories. This is thoughtful, subtle, realistic reflection on the dynamics of adult gay relationships. Boyfriends. Whereas "Weekend" examined a brief affair with the potential to grow into a long-term relationship, "Lights" depicts a long-term relationship -- with many ups and downs. But not for a second is it melodrama. Writer/director Ira Sachs, who made his first feature film, "The Delta," about 15 years ago (which I haven't seen), brings to life the story of two well-educated Manhattanites who have an anonymous sexual encounter that grows into a 10-year relationship. One is a documentary filmmaker; presumably this at least to some degree represents Sachs himself. The other is a literary agent and book editor. Thure Lindhart, a Danish-born actor, plays the filmmaker. Lindhart took my breath away two years ago in the Danish film "Brotherhood," which was on my Top 10 List of 2010. It's fantastic to see him breaking into American cinema. I guess I wasn't the only American who noticed "Brotherhood." Zachary Booth plays the literary agent. Booth is perhaps most recognizable as Glenn Close's son in the brilliant TV show "Damages." After a few years of relative happiness, the relationship runs into serious difficulty when the literary agent drifts into drug abuse. The film doesn't slip down the rabbit hole of lurid drug voyeurism. We don't go along with this man on his weekend-long drug binges. The film is mostly concerned with the emotional wreckage that results after the binge is over. We see the aftermath, not the drug binge. There's only one scene that depicts one of the binges. And here again, the focus is not on the binge itself so much as the emotional responses of the sober boyfriend who witnesses it. The film also nicely explores the ways that the filmmaker gets emotional support from his diverse circle of family and friends. But unfortunately the analysis in "Lights" never cuts that deep. It's thoughtful but only in a sketchy way. It hints at ideas more than explores them. The film also is not edited that well and starts to feel repetitious after a while. There's no denying, however, that "Keep the Lights On" is one of the better films of 2012 and a wonderful addition to what will hopefully grow into a sub-genre of serious gay cinema.