to carry to extremes; to go to the end of something; to reach the peak of something (e.g. luxury, hardships, etc); to be extremely (e.g. busy); to exhaust completely; to have nothing left (e.g. to say)
Examples (1 in total)
この任務を完了するのは困難を極めたことは言うまでもない。
It goes without saying that it was supremely difficult to carry out this mission.