Infinity Challenge(Korean) English sub-titles by KSON 1280x720p Ep 401-410

Infinite Challenge (a.k.a. Muhan Dojeon; Hangul: 무한도전; hanja: 無限挑戰; abbreviated as 무도 Mudo) is a Korean television entertainment program, distributed and syndicated by MBC. As of January 2013, it still has the largest market share for its timeslot; roughly between 13 to 17 percent of Korean television viewers watch Infinite Challenge at 6:30 PM every Saturday night. This makes it the top free-to-air television program on Saturday evening, and it's also the most viewed non-drama program in South Korea every week (excluding special sporting events, since November 2006, with the exception of January 2009, April and May 2010[4]).[5] It has kept the same scheduled time, since first airing in 2005. Since 2009, it lasts for roughly 75 minutes, excluding ten minutes of advertising. Episodes are also frequently rerun on several Korean cable broadcasting channels. Infinite Challenge have been called the nation's variety and Korea's real first variety for having been successful for over nine years.

Yoo Jae-suk As host-in-chief, he led all Infinite Challenge members in attempting to reach the goal of each episode. In 2008, he was temporarily replaced by Park Myeong-Su, but was reinstated as host-in-chief several weeks later.

Park has continuously proclaimed his nickname (Geo-seong, or Giant Star). He is often referred to as "Father" by the rest of the members due to his elderly look and his position as the oldest member of the program. This is especially prevalent when Myeong Su's receding hair is flattened or his make-up is removed. See his page for more details. His (on-air) persona is that of a veteran grumpy "upperclassman" of the other members. He often shouts or reprimands his "underclassmen," usually about humorously trivial matters.Thanks to his current work as the co-host of Infinite Challenge, Park Myung-soo gained more than 250 nicknames throughout his appearances on the program as listed by the netizens.

Haha was long considered the cutest and best-looking member of the cast. He is also the most-educated member, having obtained a Master of Arts in Theatre & Film at Daejin University; however, during the episode of the 50th special, he got only 20 points on a 100-point elementary-level spelling test. In episode 62 of season 3, he sang a song called 'A Little Boy's Story' (키작은 꼬마 이야기) as a tribute to his short height, which is a constant target of ridicule among the cast. It was a huge sensation with viewers. Haha temporarily left the show from March 2008 through March 2010 in order to fulfill his mandatory military service. In his final episode before entering the service, Haha performed at a guerilla concert that was secretly organized by his fellow co-hosts.

A comedian by profession before joining the team, Jeong Hyeong-don used to appear in the Korean comedy show Gag Concert (where Do-Re-Mi Trio being one of his many skits). However, over many episodes, he has demonstrated remarkable talent in everything imaginable (for example, catching grapes with his mouth or playing a Korean jump-rope game) except being funny. He is teased by the other members for this.

Jeong Jun-ha character is defined by the ability to make anyone around him feel awkward. His character is mainly defined by 3 things: his size (often referred to as being 0.1 tons, or 100 kilograms), appetite, and a degree of slowness in judgment. His extraordinarily large head (supposedly 8 kg) has gotten him, on a few occasions, called "Chivas Degal" (Degal = is a shortened word for "Degari", a vernacular word for "head"). In the 50th episode special of season 3, he was challenged to eat 50 plates of noodles in five minutes. The plates altogether weighed about 10–30 kg. (He succeeded, but had to go straight to the lavatory and subsequently slept in the back of the studio). On episode 61 of season 3, he went to a hair salon with Hong-chul to curl Hong-chul's hair. He asked a woman who was working there if she knew Jun-ha's name, but she said Joong-ang by mistake. Since that time, the members, including the creator Yoo Jae-suk, have frequently teased him as Mr. Jeong Joong-ang (정중앙씨), which means 'Mr. Square-in-the-middle'.