The Commuter Liam Neeson, Vera Farmiga, Patrick Wilson. Directed by Jaume Collet-Serra. Rated PG-13. Opens Friday citywide.

The fourth collaboration between Liam Neeson and director Jaume Collet-Serra, The Commuter continues in the tradition of their previous work (Unknown, Non-Stop, Run All Night), with some swift action, some creative visual touches and a committed lead performance from Neeson, built around a far-fetched high concept that gets sillier and more convoluted as the movie progresses. In this case, Neeson’s Michael MacCauley is a former NYPD officer and current insurance salesman who’s just been laid off, when he’s approached on his commuter train by a mysterious woman (Vera Farmiga). She offers him $100,000 to identify and tag a specific passenger on the train who doesn’t belong, and before he can answer, Michael finds himself drawn into a ridiculous conspiracy, his wife and son threatened if he doesn’t follow orders.

The less Michael knows, the more exciting the movie is, as he continuously moves back and forth across the speeding train, desperately trying to find the person he’s meant to target, while simultaneously trying to figure a way out of his predicament. Farmiga, who delivers most of her performance over a cell phone, is sweetly menacing as the preposterously omniscient villainous mastermind, and as always Neeson manages to deliver the most absurd lines with gravitas. As he did with the airplane in Non-Stop, Collet-Serra deftly glides his camera around the train, giving the action a clear sense of space. He stages a clever, innovative opening sequence with jump cuts conveying the passage of time as Michael takes the same commute to work every day, while life keeps happening around him.

But that level of creativity dissipates as the movie goes on, and once the breakneck pace of the speeding train stops in the third act, all that’s left is the increasingly elaborate and idiotic conspiracy storyline, which Michael has to unravel. Screenwriters Philip de Blasi, Byron Willinger and Ryan Engle throw in a vague thematic thread about economic unrest, but it never really goes anywhere, and it’s overshadowed by the action and the (often painfully obvious) plot twists. Neeson and Collet-Serra have honed this style of thriller to its basic essence over the course of four movies, with all the strengths and faults that go along with it.