'There are so many histories in the ocean'
'There are so many histories in the ocean'

For the Black scuba divers who formed the organization, Diving With a Purpose, their goal is to restore the nearly 500 voyages shipwrecked during the slave trade to the historical record.

For more, watch CNN Films’ “Lessons from the Water: Diving with a Purpose” Saturday, August 7 at 9:30 p.m.

ET.