In San Juan, you take a submarine adventure down to explore a sunken ship. As you dive below the surface, something goes wrong. The submarine powers down and you sink to the seabed. Can you power up the submarine and return to the surface?
This is extra-challenging, because the puzzle image isn't the same as the boxtop picture, and you have to decipher the clues on the in-box leaflet too.
You can get extra clues by scanning the QR code - and if all else fails, use the final answer provided in the sealed envelope.
Can you discover the 8 mysteries hidden within the puzzle and live to see another day?