“The One I Love” is one of the harder movies to review because it really helps to go into it with an open mind. The less you know about what happens in it, the better the experience will be. Ever since its debut at the 2014 Sundance Film Festival, its most fervent admirers have been praising it and guarding its secrets as if they have the secret formula for Coca-Cola. What I can tell you is that it is an insanely clever romantic comedy, and it belongs to a genre I typically live to avoid.

Things start off with the married couple of Ethan (Mark Duplass) and Sophie (Elisabeth Moss) going through troubles which usually tear a couple apart permanently. They try to recreate their romantic spark by revisiting the house they snuck into when they first met and jump in the pool, but the magic isn’t there. In the process of visiting their therapist (played by Ted Danson), he suggests they spend the weekend in this cottage he knows about so they can work on their marriage. When they get there, they find the cottage is in a beautiful location I would personally love to visit sometime, and it proves to be a very relaxing place for a vacation. But when they start to explore the other parts of the house, things quickly get very trippy.

So that’s it. This is all I am going to tell you about the plot of “The One I Love.” It is very nice we have a movie like this one where film buffs are not investigating every little detail like they do with “Star Wars” or “The Matrix.” With big blockbusters, everyone is analyzing every single moment of the movie trailers, following news updates of who is being cast, and it gets to where they have a vision of what it is going to be like inside their heads. The problem is, going into anything with such lofty expectations will usually have you living very disappointed, and perhaps for the wrong reasons. It helps that “The One I Love” is a low budget feature which is coming in under the radar because people aren’t busy overanalyzing like this one.

It should also be noted how director Charlie McDowell and writer Justin Lader created this movie out of a 50-page document which contained the scene beats and the locations of the entire movie. The only thing this document did not contain was the dialogue, and the actors ended up improvising it themselves. Even though the actors were given ideas to work with, they pretty much drive this movie more than anyone else, and I applaud the challenges they face here and the risks they took with what they were given.

“The One I Love” serves as a terrific acting showcase for its stars Mark Duplass and Elisabeth Moss, both of whom get to explore different levels of their characters throughout the movie’s running time. Mark is, of course, well known for making and producing many offbeat films with his brother Jay Duplass like “Cyrus,” “Baghead” and “The Puffy Chair” among others. As an actor, he is perfectly cast in the role of an everyman husband who finds himself threatened with the various events he is forced to endure while staying at the cottage. As Ethan, we sense his desperation to save his marriage, and we also sense his desperation to not be second best at anything.

Moss has had quite the ride in recent years with her work on “Mad Men,” “Top of the Lake” and “The Handmaid’s Tale,” and she is currently experiencing great success on the silver screen in “The Invisible Man.” She once again proves just how wide her acting range is as Sophie. Like the movie, she is full of surprises and such a lovely presence to watch, and she renders every emotion you see Sophie going through as being totally genuine. Considering what the role has her doing, it is really quite a feat when you realize what Moss has accomplished here.

“The One I Love” is one of the few movies I have seen in recent years which takes turns I did not see coming, and I honestly have not been this riveted by a romantic comedy since “Four Weddings and a Funeral.” Seriously, you really need to check your expectations at the door when you go and see it because there will be no easy way to prepare you for what will unfold. I am always waiting to see a movie which constantly surprises me throughout, and this is one of them.

If there were any expectations I had with “The One I Lovie,” it was that I was to hear Stephen Still’s song “Love the One You’re With” play over the end credits. Once you watch this movie, you will understand why this would have been the perfect piece of music to end things on. After all, “The Simpsons” made great use of it on one of their “Treehouse of Horror” episodes.

* * * ½ out of * * * *