Starring in back to back Best Picture winners Birdman and Spotlight restored some cache to Michael Keaton, whose career had been on a natural decline since the 1990s when he last played Batman for Tim Burton. No longer stuck playing the Dad of heroines in movies like Post Grad and Herbie: Fully Loaded, Keaton has recently found himself tackling the lead role of the Ray Kroc biopic The Founder and the villain of the warmly-received Spider-Man: Homecoming. Now, Keaton shares diagonal billing with Dylan O'Brien in American Assassin, an action film it's tough to imagine getting a wide theatrical release without the Hollywood veteran onboard.

Assassin is a film you could easily see going direct-to-video with Keaton's role being occupied by the likes of Nicolas Cage or John Travolta. Instead, the in-demand elder pro lends a slight air of respectability to a production that wouldn't stand out among direct-to-video fare.

The film opens with some partially first-person footage of Mitch Rapp (The Maze Runner's O'Brien) at a beach with his girlfriend Katrina (Charlotte Vega). With cell phone in hand, he documents his oh-so-cute in-ocean proposal to her. She accepts, the beach breaks out in applause and our suspicions are soon confirmed that the only reason we're opening with this is for her to get killed in an incident that will motivate our hero. Eight months after the deadly attack by Muslim terrorists, a now heavily bearded Mitch sets out to infiltrate a Middle Eastern terror cell.

As his knowledge of the Quran is being tested and he is about to unleash the wrath of God on these hateful zealots, the CIA bursts in and does it for him, saving him in the process. Reluctantly, Mitch is persuaded to join forces with the intelligence agency's counterterrorism unit. He is taken under the wing of Stan Hurley (Keaton), a grizzled, lethal warrior who pushes the young man to channel his anger for good.

Soon, Mitch is teaming up with the alluring Annika (Shiva Negar) to try to take down Hurley's rogue alumnus Ghost (Taylor Kitsch), who has a hand in obtaining some Plutonium that Iran is hoping to turn into nuclear weapons.

We don't need to discuss the plot any further than that, because it's really just an excuse for Mitch to take out his hostilities. His fiancée got murdered in gruesome fashion in the first and most memorable scene of the movie. The rest is little more than Mitch doing what he can to avenge that, by taking out extremists before they can take out more innocent people.

There is nothing graceful or original about this film, which hails from Michael Cuesta, the director of the little-seen 2014 Jeremy Renner vehicle Kill the Messenger, and a quartet of seasoned screenwriters adapting the 2010 novel of the same name, the eleventh entry (but first chronologically) in the series by Vince Flynn, who passed away from prostate cancer in 2013 at just age 47. The book series lives on, with Kyle Mills taking over the reins. But the appeal is hard to see on screen, comparable to if someone other than Tom Cruise had been cast as Jack Reacher.

Despite its consistently mediocre nature, the film was met by applause at the advance screening I attended. Enthusiasm from general public moviegoers relishing an opportunity to see a movie free and early is common. Applause at the end credits is not. Perhaps the reaction can be traced to the fact that the screening was in the same Minnesota metropolis that Flynn had called home his entire life. In fact, a special premiere was held here the Friday before this more ordinary weeknight screening.

With no knowledge of the source text, Assassin left me cold and unmoved. Sure, there are worse action movies out there, but this one never manages to stand out in a good way.