The following is based on and has not been confirmed by cut content Fallout 3 canon sources.
Infiltration is a main quest in which was cut from the final game. Its quest stages can still be found in the game files but beyond that there appears to be nothing left of it.
In this quest, the player 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.
editor ID is "MQ10". The prefix MQ designates it as a main quest and the number places it between The American Dream (MQ09) and Take it Back! (MQ11).
Quest Stage Log Entry
10 Enter Rivet City through the underwater diving hatch.
20 Obtain the prototype power source.
30 Return the prototype power source to Scribe Rothchild at the Citadel.
40 Meet with Elder Lyons in his solar.
Infiltration was cut from the final release of .