Did Atlantis exist, and can MQ find it? To answer the first question, the show looks from Bimini to Santorini. Divers check out the Bimini "Road" in the Bahamas - despite a scientist's assurance that, indeed, sometimes nature does produce straight lines. Can the team find evidence that the road was worked by human hands? They find what looks like a stone anchor, but they can't test it because it's covered with protected coral. The idea that this could be Atlantis (rather than a local civilization) is based on the predictions of Edgar Casey -- which are now so revered as to be taken as fact, rather than conjecture. Later, the team finds a "leveling stone" which they believe indicates the "road" was once a harbor -- but is it old enough to be Atlantis? (10,000 years, according to Plato.) As they test the rock for date, they go diving on another site. They find strange, regular-seeming formations on the sea floor, but the protected corals prevent further probing. The rock dates to around 1500 BC -- 8000 years later than Atlantis' alleged date. (Though similar in timespan to Minoan Crete -- though the show fails to mention this.) The other formations seem to have perfect right angles, making them appear man made, but special permission will be needed to clear the coral and find out for sure.
Meanwhile, another team investigates Crete & Santorini, on the theory that Atlantis could have been based on the ancient Minoan civilization -- which had hot and cold running water when most of their neighbors were still living in crude huts. Their theory is that the Minoans were destroyed in a single day, and therefore became the basis of legend. Santorni (then Thera) was destroyed 1600 years <
The show ends by suggesting that the Bimini Road may have been built by Atlantis' descendants, a lost civilization -- and the older formation (on the now-sunken shore of the once-much-lower sea) could be Atlantis itself. Sadly, if the MQ team will gain the permission to find out, remains for a future episode. Also sadly, aside from the blast/wave tests, the theory of Thera/Santorini-Crete being the origin of the Atlantis legend (a theory I, personally, favor) is not explored or tested any further.
Note: Edit to correct date to BC (BCE), rather than 1600 years ago (which would have been 400 AD/CE).