A clever pun can make the difference between a so-so phrase and a memorable one. The phrase “the last straw” refers to an old fable about too many items in a load, but it takes on a whole new meaning in a public-awareness campaign about...
The phrase throw in the towel, meaning to give up, originated in the world of boxing. An earlier phrase from the same sport that carried the same metaphorical meaning is chuck in the sponge. This is part of a complete episode.