From Halopedia, the Halo wiki
On November 2, 2525, Demos and Lieutenant Commander Jack Hopper 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. Demos suspected Cole was drunk - a supposition supported by several empty bottles of Finnish black vodka in his living room. They presented him with the preliminary reports of the Covenant attack on Harvest. Cole offered them a drink, 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 Demos and Hopper to reflexively stand at attention.
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