It's rather a confidential mission I'm undertaking for a friend.

The recruits' final, highly confidential mission is to win the trust of each other's nearest and dearest.

With their training now complete, the trio must undertake a final confidential mission abroad, working against professionals.

In October 1631 he was employed on a confidential mission to the Netherlands.

Then I learned of a confidential mission I could apply for.

Said they were on a confidential mission for Helder.

It was surmised that he had been entrusted with some confidential mission by the English government.

Your confidential mission is to cover their backs while they are out of town.

In 1795 he was engaged on a confidential mission to Brunswick and Berlin.

The year following he was again sent to Europe on a confidential mission.