Marco and the Pharaoh's Curse

The Beatrice sank in the Mediterranean Sea two hundred years ago. Lost to the world until now.
Divers are preparing to plunder her ancient treasure unaware that any interference with the unusual contents will trigger a catastrophic event.
The terrifying consequences of the divers succeeding are unimaginable.
Twelve-year-old Marco and a mermaid, Lois, are the only ones who can prevent it. Have they overestimated their abilities?
They have 48 hours to journey the treacherous underwater route from Malta to Sardinia to fetch help and then return.
Time is tight, but that s the least of their problems