So seriously in fact, that he is intent on protecting his co-star Maggie Grace (who plays Kim) in real life too.
"I was kind of a kiddo in the first [Taken film]," Maggie told American chat show host Conan O'Brien.
"He's like the best fake movie dad any girl could ask for. I mean he's so protective. In real life too."
Maggie then revealed that when she told Liam about an ex-boyfriend who left her 'a little bit heartbroken,' he decided to cheer her up by prank calling the unnamed heartbreaker.
Liam assumed the persona of his tough Taken character and called Maggie's ex at his office.
"This is Bryan Mills," the Oscar nominee said. "We've never met, and if you play your cards right, we never will."
"Now listen (bleeped out expletive), you're lower than the pond scum so I'm just going to say this once.
"You've made two mistakes: Your first mistake was dating out of your league. Your second mistake, well, let's just say any more mistakes and I'll break your other arm – slowly.
"I don't need to say it, but I have a particular set of skills," Neeson added, quoting one of Bryan Mill's most famous lines.
"And I don't want to waste them on you. Now you get your s--t together."
Luckily Maggie had the foresight to record the call, so you can hear Liam in full-on protective dad mode for yourselves in the clip below.
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Liam has two sons - Micheál, 19, and Daniel, 18, - with his wife Natasha Richardson who was killed in a skiing accident in Quebec in 2009 at the age of 49.
We imagine any ex-girlfriends of Micheál and Daniel must be quaking in their boots right now!
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