Kelly Brianne Clarkson (born April 24, 1982) is an American singer, songwriter and occasional actress. Clarkson came into prominence after becoming the winner of the inaugural season of the television series American Idol in 2002 and later was the runner-up in the television special World Idol in 2003.

In 2003, Clarkson released her debut album, Thankful, which was a commercial success and established herself in the pop music industry. The release of its first single, "A Moment Like This" (2002), broke The Beatles' record for the biggest leap to number one, from 52, in the history of the Billboard Hot 100 chart. After parting ways with her management, Clarkson developed a more rock-oriented music with the release of her critically acclaimed sophomore album, Breakaway (2004), which sold more than 12 million copies worldwide and which garnered Clarkson more worldwide success as a pop rock artist. The album's single, "Because of You" (2005), became the best-selling single by an Idol contestant worldwide. In 2007, Clarkson took full creative control for her third album My December, which had a more rock-inspired sound and was met with controversy and moderate success. Clarkson later returned to a more pop-oriented sound with All I Ever Wanted (2009), which became a commercial and critical success. The album's lead single, "My Life Would Suck Without You" (2009), surpassed "A Moment Like This"'s record for the biggest leap to number one on a single week in the history of the Billboard Hot 100 Chart, a milestone it still holds today. Furthermore, it also became her first number one single in the United Kingdom. Clarkson's fifth studio album, Stronger, was released in 2011, containing elements from synthpop, R&B and country music. The album's single, "Stronger (What Doesn't Kill You)" (2012), became her longest number one single and eventually became her best-selling single in the United States.

Leona Louise Lewis (born 3 April 1985) is a British singer and songwriter. Lewis came to prominence in 2006 when she won the third series of the British television series The X Factor.

Lewis has released two albums to date, Spirit and Echo, in 2007 and 2009 respectively. A multi-platinum selling artist and three-time Grammy Award nominee, her most successful single, "Bleeding Love", reached number one in over thirty countries around the world, and was the best-selling single worldwide in 2008. Other notable singles include "Better in Time", "Happy" and "I Got You". She was proclaimed 'Top New Artist' by Billboard magazine in 2008.

Lewis's debut tour, The Labyrinth, took place in 2010, and her third album, Glassheart, is scheduled for release in 2012. It was preceded by "Collide", a single from the album, which became her seventh top-five hit in the United Kingdom. Lewis's net worth was estimated at £12 million in April 2012.

David Michael Letterman (born April 12, 1947) is an American television host and comedian. He hosts the late night television talk show, Late Show with David Letterman, broadcast on CBS. Letterman has been a fixture on late night television since the 1982 debut of Late Night with David Letterman on NBC. Letterman recently surpassed friend and mentor Johnny Carson for having the longest late-night hosting career in the United States of America.

Letterman is also a television and film producer. His company Worldwide Pants produces his show as well as its network follow-up The Late Late Show with Craig Ferguson. Worldwide Pants has also produced several prime-time comedies, the most successful of which was Everybody Loves Raymond, currently in syndication.

In 1996, David Letterman was ranked #45 on TV Guide's 50 Greatest TV Stars of All Time.

Letterman was born in Indianapolis, Indiana. His father, Harry Joseph Letterman (April 1915 – February 1973), was a florist of British descent; his mother Dorothy Letterman (née Hofert, now Dorothy Mengering), a Presbyterian church secretary of German descent, is an occasional figure on the show, usually at holidays and birthdays.