Colin Moriarty

Colin Moriarty is Megaton's crime boss and the owner of Moriarty's Saloon, and speaks with a slight Irish accent. He has a computer which contains valuable information on the game's main quest. To access the information, you can either pay Moriarty for it, get the info from Nova, the local prostitute working for Moriarty, or convince Gob, the ghoul bartender, to tell you how to access his boss' computer. The player can also go into sneak mode, pickpocket Moriarty's key from him, use it to open a cabinet in the back that contains his computer's password and gain the information that way. If you pay Jericho 20 caps for information, he will tell you that Moriarty keeps the payroll for Nova and Gob locked by his bed. Moriarty's bed is located upstairs in his saloon. Jericho informs you that Moriarty keeps the key around his neck.

Unfortunately, in the unpatched release version of Fallout 3, this key appears to be missing for some users playing the PC version of the game and cannot be pick-pocketed, However some other PC users have no such bug.

Appearances
Moriarty appears only in Fallout 3.

Behind the scenes
Colin Moriarty is also a writer for the gaming news site, IGN.com and in one of his own Podcasts (Three Red Lights Ep. 44a) he says the character in Fallout 3 is named after him due to his status in the gaming community. He is a writer for the website of many gaming FAQ's. He has said that writing the FAQ for Fallout 3 will be very difficult for him. For more information on IGN's Colin Moriarty, see http://faqs.ign.com/articles/378/378384p1.html

Known Bugs and Solutions
Moriarty has been reported to disappear into the wasteland making it difficult to complete the main quest. To determine if this has happened, select a quest involving Moriarty as the target (generally Following in His Footsteps), then bring up the World Map. If the marker for Moriarty appears north-east of Springvale School, then you can safely assume he has wandered away. This can be a dealbreaker for players who wish to do play with Good Karma, as the alternate solutions involve talking the information out of Gob or Nova and potentially hacking Moriarty's computer, though the small amount of negative Karma can easily be countered by simple tasks like giving scrap metal to Walter, giving water to Micky, or donating money to the Children of the Atom. Alternatively a player can simply wait and finish Following in His Footsteps by visiting Rivet City during the The Wasteland Survival Guide quest and speaking with Doctor Li. This results in no karma loss and the added benefit of discovering Rivet City relatively early in the game.

While playing PC version you can also bring him back by following Recovering missing NPC in Fallout 3 guide.

Using the Mesmetron on him will have the same effect on all non aggressive npcs. However even though he dies, the other npcs in the town will all act as if he is alive and you will still get the objective to talk to him about Dad.