The Big Bang Theory has finally grabbed the ultimate science guest star.
Renowned physicist Stephen Hawking will appear in the sitcom next month, after the famed research director at Cambridge University's Centre for Theoretical Cosmology filmed a cameo on the show last Friday.
According to US magazine TV Guide, the plot will see the 70-year-old physicist play himself in a "run-in" with Jim Parsons' character Sheldon.
"When people would ask us who a 'dream guest star' for the show would be, we would always joke and say Stephen Hawking - knowing that it was a long shot of astronomical proportions," producer Bill Prady said in a statement.
"In fact, we're not exactly sure how we got him. It's the kind of mystery that could only be understood by, say, a Stephen Hawking."
Hawking has previously appeared as himself, or at least as his own voice, on The Simpsons and Futurama.
The episode is due to be broadcast in the States on April 5.
It will air a week after fans witness another Big Bang breakthrough, when Leonard Nimoy appears on the show as his Star Trek character Spock, in a dream sequence.
TVNZ has started screening the 5th season of The Big Bang Theory but are a couple of months behind with the episodes.
-Sydney Morning Harald
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