Here is the full list of all 26 Overboard! achievements.
Clean someone out at cards
Everything ship-shape in 4 hours or less
Everything ship-shape in 5 hours or less
Money, man and murderer in 2 hours or less
Get off in 3 hours or less
Discuss literature with the highest authority
Everything ship-shape and Bristol fashion
Put an old lady to sleep
Get off in 5 hours or less
Money, man and murderer in 5 hours or less
Talk someone down
All of Malcolm's possessions, into the sea
Get your way the hard way
Seven down
Six down
Five down
Four down
Three down
Steer the ship
Reunite with Malcolm
Two down
Earn a small fortune for your efforts
Allow the killer to escape from justice!
Get yourself a nice man
Establish relations with an officer
Get the killer sent to prison