Architect JD (John Lloyd Cruz) has a chip on his shoulder about his businessman father Rico (Ronaldo Valdez) never really accepting him as his son. Seamstress Sari (Bea Alonzo) struggles to take care of her family. The two meet by chance, and JD aggressively pursues Sari's affections. Though the two are clearly a good match, there is a problem standing in the way of their bliss: Sari is the mistress of JD's father. Against his better judgment, JD continues to court Sari even after finding out this difficult fact. He hides his true identity as Rico's son, and fights to win Sari's heart.
The movie isn't as complex as the premise makes it sound. Though it tackles mature subject matter and plays with Oedipal themes, the film is really much more about the love story than it is about the adultery. It focuses largely on the courtship, lingering on scenes of JD and Sari being nice to each other. It doesn't really do enough to flesh out her relationship with Rico, and that makes her choice feel like a foregone conclusion. The film might have benefited from a closer examination of their arrangement, digging into the psychology of the characters and showing what makes the relationship worth committing to. As it stands, her commitment to it feels a tad contrived.
Given that, the film is still occasionally great. Its loveliest parts ask the characters to pretend that context doesn't exist, and it lets them indulge the fantasy. The movie nimbly plays between tones of sweetness and tragedy, gathering emotion from the impossibility of these characters escaping who they are and what they’ve done. In these moments, the film creates such a compelling case for their romance that it's easy enough to let the rest of it go. Lamasan has such a grasp of what makes romance work on screen, setting the mood and giving her actors the room to maneuver. A couple of badly structured sequences and continuity errors don't entirely detract from the overall effect.
In the end, it all boils down to chemistry. And there's really something magical between John Lloyd Cruz and Bea Alonzo. The two share a strange edginess that lets them transcend the tropes of the onscreen couple. Alonzo’s visible pragmatism lends credence to her claims of love. And Cruz feels close to a breakdown, using a false confidence to hide the pain that lies within. Together, the two are endlessly watchable. Little is done with the supporting cast. Ronaldo Valdez doesn’t get the time to get anywhere past bluster. And Hilda Koronel gets oddly cartoonish at points.
It’s difficult to buy the whole arc of The Mistress. It just isn’t fleshed out enough, the film presenting premises without elaboration, allowing certain characters to work only within the limits of cliché. But at times, that context doesn’t seem to matter. At times, the film is just about two people in love who can’t be together. The reasons are less important than what is produced in moments, sparks of romance that transcend that need for context, thriving on the universality of the need to pretend. It still doesn’t work as a whole, but The Mistress still makes a compelling case for itself every now and then.