Infiltration

Infiltration is a main quest unused in Fallout 3. Its quest stages can still be found in the game files.

Overview
In this quest, the player character was supposed to enter Rivet City through an underwater hatch, acquire the energy source of "the prototype" and return it to Scribe Rothchild in the Citadel. The final objective was to meet Elder Lyons in his study.

The quest's editor ID is "MQ10." The prefix MQ designates it as the main quest and the number places it between The American Dream (MQ09) and Take it Back! (MQ11).