Received from: automatically after accepting a mission from the Chanter's board [Denerim - Market district]
Description: You can complete this mission while trying to end one of the main quests - Saving the queen. To be more precise, you must make your way to [Denerim - Arl of Denerim's Estate - Dungeon] and start exploring the underground complex. Check one of the rooms located in the eastern section of the dungeon (M74, 4), marked as the lower prison level. Start off by eliminating a prison guard (mini-boss) and once he's gone check his body for a prison key.
You can now proceed to the next room where you'll find a couple of cells. Locate the cell where Rexel is being held (M74, 5). Naturally you shouldn't kill him during the initial conversation. Instead find out more about who he is. You can't do much to help him, however your journal is going to be updated. You can also meet the other prisoner while you're there (M74, 6), but it's optional. In order to end this quest you must return to [Denerim - Market district]. Go to the board and talk to Rosamunda to tell her about Rexel's fate.