Recommended reading: Lost Continents, by L. Sprague deCamp. A very thorough exploration of every turn the Atlantis/Lemuria/Mu meme has taken over the years, from Plato to Blavatsky to Ignatius Donnelly to Cayce, with appropriate debunking. A thoroughly fascinating piece of work.
Atlantis apparently started life as a political/philosophical allegory created by Plato and provided with a believable fictional background (information brought by Solon from Egypt, imparted to the grandfather of someone at the dinner at which the dialogue is set). Aside from a couple of then-exposed now-submerged coastal areas in the Azores and Bahamas dating from the Pleistocene or before, there appears to have been no submerged lands in the Atlantic, and certainly no advanced ancient mid-Atlantic civilization drowned in a cataclysm.
Insofar as there might be a historical analog to the Atlantis story, the destruction of the Minoan civilization by events associated with the Thera eruption (a Krakatoa-style catastrophic eruption) matches in some amazingly accurate ways – provided that you assume an exaggeration factor of ten on both temporal and spatial number cites, and ignore some inconvenient details as being Platonic pontification superimposed on the legend.