Every year, the annual E3 video-game expo kicks off with media briefings by the three console makers: Microsoft, Nintendo and Sony.

The trio vie to get the most buzz for their games and products by trying to one-up each other with the most entertaining, star-studded show they can muster up.

Microsoft, who kicked off E3 Monday morning, set a high bar this year with a media briefing that was preceded by a mysterious e-mail the day before.

That e-mail stated that the event would start five minutes early "due to a very special addition."

Its special surprise guests turned out to be the Beatles' Paul McCartney and Ringo Starr, as well as the spouses of the late John Lennon and George Harrison, Yoko Ono and Olivia Harrison.

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