Dead Drops is a quest received from the Favors for Certain Interested Parties Quest Board at Gnawed Noble Tavern.
Background
"K" seeks a traveling salesman (of sorts) to drop off some booty while in several neighbourhoods.
Walkthrough
The objective of this quest is to discretely drop off "payment" for certain individuals, as contracted out by the rogue "K". The locations you must visit are:
Redcliffe Village - Past Owen's blacksmith shop, near Dwyn's house.
Lake Calenhad Docks - At the The Spoiled Princess inn.
Frostback Mountain Pass - Near Ahren, the dwarf "merchant" who won't trade with you.
Denerim Market District - Near Cesar and a cage.
Before running around Thedas, the quest will end with a choice you have to make, return to all the locations and defuse the drops, or leave them be. If you choose the former, setup the route you take to be efficient - for example, you have to go back to the Denerim Market District to collect on the quest anyway, so leave that one for last.
If you decide to leave the drops alone, return to the Bartender and collect your reward; on the other hand, if you decide to disarm them, a proficient rogue will be required to disarm the traps. After disarming them all, you can still collect your reward, but the rogue "K" will be quite upset and not offer you any more jobs.
Rewards
6 
Bugs
This quest must be completed before the Landsmeet. If you travel to Redcliffe after the Landsmeet has begun (traveled to Denerim with Arl Eamon), but before the Landsmeet's conclusion, any save file after that will be corrupted and will not load.
Note: I've just attemted this and am able to load my save data. I'll leave this here as others may still experience it.