The Reefer Madness Add-on for L.A. Noire (Xbox 360) has 5 achievements worth 100 gamerscore.
Complete 'Reefer Madness'.
Complete the puzzle of the US Morgan silver dollars at Parnell's Soup.
Open both soup cans in Juan Garcia Cruz's stash room.
Find the flyer at Juan Garcia Cruz's house and proceed straight to the 20th Century Market.
Enter the Las Palmas stash house via the back door and kill Juan Garcia Cruz.