The Cleaner

 is a miscellaneous quest in Fallout 4.

Quick walkthrough

 * 1) Buy an alcoholic drink from Whitechapel Charlie.
 * 2) Accept the quest from the ensuing conversation.
 * 3) Go to the  all 3 Goodneighbor warehouses. Kill all enemies inside.
 * 4) Return to Whitechapel Charlie to collect the reward.