The Birds and the Bees Affair - S2.E18

THRUSH has developed with the aid of Dr. Elias Swan, a strain of minute, deadly bees. THRUSH agent Mr. Mozart captures Illya and Tavia Sandor and uses a high-frequency sound machine that threatens to shatter their eardrums to force Illya to take him to U.N.C.L.E. headquarters so he can release the bees. Illya does so, but Mozart is intercepted, and in a battle on a rooftop Mozart is shot and the bees get loose.