go down with the ship

1. To die because one was aboard a ship that sank. A ship's captain, in particular, is traditionally expected to remain on board a sinking ship in order to save as many other lives as possible. Some of the sailors were rescued, but the majority of the crew went down with the ship. No, you save yourselves. I'm the captain, and the captain goes down with the ship! In a horrific storm like that, it's possible that the entire crew went down with the ship.

2. By extension, to fail or be punished as a result of one's involvement with some larger group or enterprise. With all this evidence coming out against the senator, the people in his office better think carefully before they speak out in support of him—otherwise, they're liable to go down with the ship. I'll go to the police about the CEO's cover-up if it means avoiding jail—I refuse to go down with this ship! Why are these people so loyal? Why would they go down with the ship after finding out their boss is suspected of tax evasion?