"24: Live Another Day" cast Kiefer Sutherland expressed surprise with the popularity of his catchphrase "damn it!" as he joked about his character not being able to curse by the censors but allowed to kill people.

"24: Live Another Day" cast Kiefer Sutherland appeared on "The Tonight Show" where he told Jimmy Fallon that they were really surprised by the way the catchphrase has caught on with the viewers of the series.

"We never meant it to catch on like it did," he said.

The 47-year-old actor explained that the catchphrase "damn it!" was created out of necessity so Jack Bauer can expressed his frustration without really violating the rules against cursing.

"There's no other expletive you can use on network television. Really there isn't a single other one," he told Jimmy Fallon. "There were so many moments from the very first day we shot to know where, not only as a character, but myself as a person, needed something to get out of the scene and so that seemed to be the word.

According to TheWrap, Jimmy Fallon managed to find one enterprising viewer who compiled how many times "24: Live Another Day" cast Kiefer Sutherland uttered "damn it" throughout the nine seasons of the series, including the made-for-TV movie.

Including the "24: Live Another Day," Jack Bauer reportedly said "damn it" 144 times.

"24: Live Another Day" cast Kiefer Sutherland, his character reportedly killed twice as many that number.

"You can't swear, but kill as many people as you want," Kiefer Sutherland joked.

The'24: Live Another Day' ratings for the penultimate episode remained flat.

The Nielsen Fast National data revealed "24: Live Another Day" news when for the second consecutive week, the 18-49 demographic for the show recorded the same numbers even if the overall viewership increased to 5.96 million.

Citing the Nielsen data, HeadlinePlanet said that Monday's episode generated 1.5 adults in the 18-49 rating with 6.00 million viewers, against last week's edition which drew 5.76 million viewers and 1.5 rating.