Mouse

I googled the quote "The best laid plans of mice and men often go astray". On Yahoo answers, someone wrote that basically, it means that no matter how well you plan something, always expect the unexpected. Just because you think you've done all you can for something to go right...something can get messed up. They suggested to always have a plan B.

We don't have a plan B. This was it. This was going to change everything.

Things have gone astray.