Los Angeles, Feb 19 (IANS): Actor Nathan Fillion, who essays the role of Richard Castle in TV series "Castle", says making people laugh is one of the biggest successes of the show.

"I think people enjoy being able to laugh at someone else’s expense, and that was a lesson I learned in my career (though I wish I’d learnt it earlier). It is very easy to make people laugh at you but it is very difficult to make people laugh. And the fact that we’ve made people laugh is one of the show's successes," Fillion said in a statement.

Asked what elements of "Castle" appeal to an international audience, Fillion said there are "universal constants" that can make the show work in other countries.

"As 'Castle' plays in Russia I think there are some cultural similarities and universal constants that make the show work -- like human relationships. Certainly, people are tuning into 'Castle' because they can relate to the homicide investigations," he said.

"I would say actually, that the engine that keeps our show running is the simplicity and the reality of the relationship between people. It is something that transcends borders and language barriers," he added.

"Castle" airs on Star World and Star World HD.