Dr Michael Mosley, 67, has now been missing for two days on the Greek island of Symi, where he was holidaying with his GP wife Dr Clare Bailey.
Police launched a massive search operation with holidaymakers and the local island community pitching in, and it's believed there are now several theories being considered.
According to reports, Greek officials have now set a deadline due to fears that the intense summer heat may have affected the This Morning doctor.
However, this isn't the only theory officials are exploring, with other suggestions including a fall from a height or even a snake bite.
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