Commander Drury of the USIA (left) confers with Maxwell Smart using "hover cover".
Method used by the United States Intelligence Agency to convey sensitive information.
Agents involved go to the roof of the building where helicopters hover overhead, their noise thwarting any would be eavesdroppers.
Unfortunately, the same noise may prevent the participants from hearing each other and, in addition, they must guard against being blown of the roof by the air draft from the 'copters' blades.
[TV Movie: "Get Smart, Again!".]