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