In 0 BBY, Grenwick acted as Sergeant Major Enfield's tactical advisor and coordinated the service schedule of the detention block. He was an interrogation technician and was present when Darth Vader interrogated and tortured Princess Leia Organa of Alderaan in her cell.
Not too long after, the first Death Star saw its destruction in the Battle of Yavin.
Grenwick was portrayed by Harry Fielder in Star Wars: Episode IV A New Hope.
- Star Wars Customizable Card Game — Special Edition Limited
- The Official Star Wars Fact File37
- "The Men Who Built the Empire" — Star Wars Insider 96
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