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