In a sense, the institute's unusual mission reflects Ms. Flanagan's own quirky life history.

Rockwell was one of six engineers selected for this unusual mission.

"Since this is such an unusual mission, am I to be dropped off on my planet before you depart?"

"I understand this is an unusual mission," he said, wiping the sleep from his eyes.

But one of his most unusual missions took place in this remote northwestern corner of the country.

On 25 May, Johnson experienced an unusual mission.

It is an unusual mission in a city where social life has ground to an almost complete halt.

During this posting, Ball undertook an unusual mission.

It was by no means an unusual mission, however.

News of the unusual mission was published, most prominently in the Saturday Evening Post.