From Halopedia, the Halo wiki
On November 2, 2525, Hopper and Lieutenant Demos were ordered to visit retired Vice Admiral Preston Cole and offer him reinstatement. Essentially it was their job to convince him to come out of retirement and command the fleet to retake Harvest. Hopper's first impression of the former-legend was that he had found the ghost of Admiral Cole, not the man. They presented him with the preliminary reports of the Covenant attack on Harvest. Cole offered them a drink of Finnish black vodka, which they took for politeness's sake. He then told them:
Cole then set his drink aside undrunk, cleaned himself up and got dressed in uniform, a transformation which caused Hopper and Demos to reflexively stand at attention. Cole immediately began issuing orders, and requested all of the intelligence reports ONI was holding back, just like Hopper had been told he would.
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