The actor’s latest action thriller, “Unknown,” took in $25.6 million during its opening weekend.

The Liam Neeson film Unknown topped the box office over the holiday weekend with a $25.6 million bow, in a surprise victory over teen entry I Am Number Four. Here are five reasons why the actor took the No. 1 spot:

1. He’s a relative newcomer to the action genre — at 58. With other action stars including Arnold Schwarzenegger, Bruce Willis and Sylvester Stallone aging, Neeson could conceivably be considered a “fresh face” in the genre — despite being 58 years old.

“Ever since big names like Sylvester Stallone, Bruce Willis and Jean-Claude Van Damme got a bit long in the tooth to making action movies there has been a battle to fill the void,” writes David Schuster of Chicago Now.

“And into the fray over the last year has been Liam Neeson. Not exactly the action star person you would expect but with Taken and now the recent release Unknown, Neeson has proven to be a pretty sure box-office attraction.”

2. But, his age isn’t showing. In both Taken and Unknown, Neeson shows that he can still throw a punch with the best of them, at times fighting multiple — and sometimes younger — attackers at once.

“When you watch Liam Neeson chase down his daughter’s abductors in Taken, shoving people up against walls or chopping them in the windpipe, or when you watch him get all Bourne again — now puzzled, now ice-cool, now angry, now really angry — in this weekend’s hit thriller Unknown, you don’t think something like, ‘Wow, he moves pretty good for a guy his age,’” writes Entertainment Weekly’s Owen Gleiberman. “You think: ‘Get the f— out of the way. He means business.’ ”

3. He reignited the action genre with Taken, and stuck to the same formula with Unknown. Two years ago, Neeson made his first big move into the action genre with Taken, which surprised box-office observers.

On opening day, the movie made $9.4 million, the best opening day ever for a Super Bowl Weekend; overall, the movie made a total of $226.9 million at the worldwide box office. The movie received generally mixed reviews, but its box-office performance suggested that moviegoers were hungry for action thrillers.

And with many reviewers noting the similarities between Taken and Unknown — and some, including The Hollywood Reporter, claiming the newer film is better than the 2009 title — it’s perhaps no surprise that fans of the first movie turned out likely expecting more of what they enjoyed the first time around.

“Although [Unknown] features the same star and, in some ways, the same framework as the Paris-based shoot-’em-up [Taken], Unknown swaps the nons for neins by changing the setting to Germany,” writes THR’s Jordan Mintzer. “It also boasts better action set pieces, a handful of convincing cameos and unexpected reversals late in the script.”

4. He’s a highly acclaimed actor — a thinking man’s action hero. Neeson has earned Oscar, Golden Globe and Independent Spirit noms for roles in films including Schindler’s List, Kinsey and Michael Collins. And despite mixed reviews for Unknown, many critics had good things to say about the star. So unlike other action stars whose characters arguably use their brawn much more than their brains, Neeson seems to inject a level of intelligence into his roles — even as he’s firing bullets and punching out foes. “Unlike Harrison Ford, who usually plays a grouch with muscles, Neeson suggests the intellect of someone who might have stayed awake in college classes; he’s as plausible as an Ivy League scientist as he is a thug for hire,” writes Time’s Richard Corliss.

5. He’s relatable. Neeson doesn’t have the movie-star good looks of say, a Brad Pitt, or the physique of an in-his-heyday Arnold Schwarzenegger. He’s got flaws, and he seems more like a guy you could bump into on the street. That makes him more accessible to audiences. Additionally, there is a good deal of public sentiment toward the actor since he lost his wife, actress Natasha Richardson, in a skiing accident two years ago. Unknown director Jaume Collet-Serra has said Neeson’s ability to connect with the audience on another level the reason he wanted Neeson to star in his movie: “The fact is in this movie you don’t have much time to get to know the character before he goes crazy. I needed someone who, in a very short time, would give us something to like him, to root for him. And I knew Liam would deliver. He has the presence. Anything he says as an actor you believe.”