Possible Clues:

• In Greek legend, a beautiful island overwhelmed by the sea
• Having reached 50, worker lives in fantasy land
• Athens attacker, in Plato
• Legendary sunken island
• The land down under?
• Lost island of Greek myth
• Fabled sunken realm
• Fictitious place social worker discovered in a sick list
• Legendary long-lost island
• In Greek mythology, an idyllic island that sank below the sea in an earthquake