It was a spy operation that could have came from a movie script.

Intelligence agencies infiltrated Al Qaeda in Yemen and foiled a plot to bomb an aircraft bound for the United States.

Remarkable work given that Al Qaeda carefully screens recruits.

The man has not been identified. However, authorities tell ABC news the spy infiltrated the terror cell posing as a double agent, learned of the plot, got his hands on a bomb, and left Yemen with it.

The device, described by officials as an upgrade to the underwear bomb that Al Qaeda has attempted to use in the past, is being studied by the FBI.