down the tubes

down the tube(s)

Awry; in a state of deterioration or failure. You got a C average? Boy, your grades have really gone down the tubes this semester. We had big plans for our trip, but the terrible weather made it all go down the tube.See also: down

down the tubes

Also, down the tube. Into a state of failure or ruin, as in If he failed the test, his chances went down the tubes. ] Colloquial; 1960s] Also see down the drain. See also: down, tube