The Thief of Midnight Badge
From City of Heroes: Rebirth - Wiki
Description
Only you and Darrin Wade will ever know what you took from the Midnight Squad. Even now they believe the artifacts they look upon with such reverence to be authentic
How to Get
The Thief of Midnight accomplishment badge can be earned by completing the Go over the plan mission from Darrin Wade.
As a Flashback arc, you must complete "Midnight Draws Near" in the Undesireable (Level 25-29) section.