From Halopedia, the Halo wiki
Thomas Wu grew up in the Outer Colonies. Considering that the colonies were a major bridgehead for Insurrectionists, Wu was kidnapped and questioned in his youth by the rebels along with many other citizens. Thomas and the others were constantly interrogated and locked in crates. The group of terrorists eventually left Wu and many others to die in a dark overcrowded crate for weeks. Many of the other prisoners died, resulting in a disturbing smell from their corpses. Thomas and the other surviving prisoners worked together to survive until they were eventually freed.
In 2558, Thomas was hired by the Office of Naval Intelligence to make reporter Benjamin Giraud believe that John-117 was also a victim of the Insurrection in order to create a fake backstory for the hero. Wu agreed to help them as long as they fund memorials and awareness campaigns for the actual Insurrection victims. On ONI's behest, Giraud called Thomas to interview him. Thomas was generally honest with Giraud, but added that Eridanus II was overrun by Insurrectionists to stay true to his deal with ONI.
Giraud called Wu a few weeks later to clear up inconsistencies with stories he had heard from other interviewees. After Giraud accused Wu of lying about Elysium City having harbored a rebel prison camp, Thomas became defensive and claimed he just wanted peace of mind for his family. Confused, Giraud tried to ask him what the interview had to do with Wu's family. Thomas then quickly hung up, making Giraud wonder if Wu's statements were reliable.
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