grave affair

"This is a grave affair, in which the intention to establish an espionage network in Israel for Iran was exposed," a Shin Bet statement said, without listing the charges against the group.

That would be a very grave affair.

The assembly was any thing but a cheerful one, and it was easy to perceive that some grave affair occupied the thoughts of all present.

Indeed, for some days Murdock has been a new man—acting as one with some grave affair on his hands—a feat to accomplish, or negotiation to effect—resolved on carrying it to completeness.

Indeed, for some days Murdock has been a new man—acting as one with some grave affair on his hands—feat to accomplish, or negotiation to effect—resolved on carrying it to completeness.