|1.||rock and a hard place|
in a tight spot; having to make an impossible decision; a lose-lose situation
Shack wants to go to her best fish's birthday, but she already promised to go out of town with her friend. she is between a rock and a hard place.
|2.||Rock and a hard place|
Having to choose between two undesirable situations
Some of David Letterman's female employees were caught between a rock and a hard place; They either had to sleep with a cranky and humorless old man or risk getting passed over for promotions by women that were.