In The Soup Meaning

Example : 1915, John Buchan, The Thirty-Nine Steps, ch. 2:  [U]nless the murderer came back, I had till about six o'clock in the morning for my cogitations. I was in the soup — that was pretty clear.1919, P. G. Wodehouse, "Jeeves and the Hard Boiled Egg" in My Man Jeeves:  [T]he poor old lad is absolutely dependent on that remittance of yours, and when you cut it off, don't you know, he was pretty solidly in the soup.1989 Feb. 13, John Greenwald, "Tiptoe Through the Tensions," Time:  "If they don't hit it off, we're all in the soup," warned Yasuhiro Nakasone, Japan's former Prime Minister, as his successor prepared to meet President Bush last week.