After starting his career on bad TV shows (“Two Guys, A Girl and a Pizza Place”) and even worse movies (Van Wilder, Just Friends), Ryan Reynolds may be pulling off the George Clooney-esque trick of getting better in his career as he gets older. Already this year he winningly played a father and a romantic lead in Definitely, Maybe, and now he’s at it again in Chaos Theory, a decidedly weaker movie that still benefits from Reynolds’ relatable charm.

Reynolds plays Frank Allen, the kind of efficiency-obsessed head case who only exists in movies. He’s made a career out of telling people how to manage their time well, and at home with his wife Susan (Emily Mortimer) and daughter Jesse (Matreya Fedor), he tries to be the organized taskmaster while Susan struggles to hang on to the free-spirited identity she had before she was married. One day Susan attempts to do Frank a favor, setting the clocks ten minutes forward to give him extra time in the morning. By mistake, she turns them ten minutes back, which makes Frank late for a lecture engagement, which sets off an entire series of events that result in Frank and Susan separating.

First, there’s a sassy stranger at the lecture (Sarah Chalke) who almost seduces him in his hotel room. Then, fleeing the scene of the near-infidelity, Frank picks up a stranded motorist about to give birth. The hospital mistakes him for the father, and after Susan receives an awkward phone call from the maternity ward, she and Frank have a series of fights that could have ended with one moment of clear conversation or explanation. It’s the kind of lunacy that flies by just fine in a farce, but in a talky comic drama like this one, it stretches credulity to the breaking point.

The message of Chaos Theory, very literally yelled out by Frank near the end, is to embrace chaos! Live your life unburdened by rules! Fair enough, but Frank is such an extreme case, planning his life to the minute, that it’s hard to take life lessons from his transformation. The real heart of the story is in the very relatable saga of Frank and Susan, how they find the need, ten years into a marriage, to learn how to live with each other all over again. Mortimer and Reynolds, with Stuart Townsend in a supporting role that builds a kind of love triangle, all depict their relationships effectively, but their characters never take complete shape within the labored plot that drags them along.

Frank’s story is told in flashback, a cautionary tale for the groom about to marry his now-grown daughter. The framing device is unnecessary, and indicative of writer Daniel Taplitz’s failure to comprehend the necessary pieces that make a screenplay work. Chaos may make for an interesting life experience, but onscreen it results in a messy and unfulfilling movie that can’t be saved by moments of sharp humor and occasional insight.