
Sherlock star Benedict Cumberbatch appears on Sesame Street this week up against Murray-arty, a nemesis even more wicked than the show's Moriarty. Cumberbatch calls in the aid of a professional, The Count, to help solve a fruit mystery and find out how to count up to four apples and three oranges. Turns out 4 apples is more than 3 oranges and Cumberbatch is 1 smart man. But he's not the first celebrity to be put up to the puppet test.
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First lady Michelle Obama sat down with Elmo and Rosita in October 2013 in the State Dining Room of the White House to help promote fresh fruit and vegetable consumption to kids. Michelle talked about healtier food choices and even compared muscles with Elmo.

In 2004, Norah Jones stopped by Sesame Street to sing about the letter Y. "I waited till I saw the sun, don't know why, Y didn't come".
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Alicia Keys appeared on the show to sing a version of her song "Falling". The alternate "Dancin", featuring vocals by Elmo, gives the orignial a run for its money.
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In pre-Twilight days, Dakota Fanning also appeared on the show to sing with Elmo and Zoe.

Another first lady to stop by Sesame Street, Laura Bush met Boombah, a cast member of the Indian version of the children's television show at their film studio on the outskirts of New Delhi in 2006.

Elmo got some imaginary exercise playing imaginary tennis with Venus Williams in April 2004.
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United Nations Secretary General Kofi Annan showed up to break up an argument between the show's characters, determining that everyone gets to sing the Alphabet Song and joining in himself.

In 1993, President Bill Clinton appeared on the show and watched Kermit sing on Hillary's shoulder at the Salute to Youth event at the Kennedy Center in Washington, DC on January 19.
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Stevie Wonder was joined by Grover to perform "Superstitious" in 1973 and his lesser known hit, "123 Sesame Street".