The Caparthia, the ship that rescued the survivors of the Titanic’s sinking, was sunk by German torpedoes during WW1 when it was part of a convoy going to Boston.
A treasure hunter named Tommy Thompson located a ship that sank in 1857 called the SS Central America. The ship carried several tons of gold, and in 1987, he recovered over $1 billion worth of gold from it. He never paid back his crew or investors, and hasn’t been seen in years.