I had a boss...
Who was know for this, I therefore kept all communications and generated email responses confirming information he relaid to me just so "I understood" what he was after.
So as inevitable, I was reassigned to another "priority task" that my boss said was to get 100% of my time and to "blow off" everyone else. The 100% task took about 10% of my time, as is typical with such things.
So when I was requested to look at another task, I had to decline per my boss. That didn't go over well and the issue escalated within an hour to the VP of Engineering. Needless to say, my boss threw me under the buss... the problem was, I was also latched onto his balls... pesky emails.
So when the inevitable meeting with the parties involved came to fruition, I had my stack of emails, quietly hidden from my boss in my lap, and the VP of engineering walk in, a decent guy. The inevitable "blame" fell on me, I reached down, garbed the folder and opened it. The blood rushing from my boss's face was classic and very satisfying to watch, as was the look of puzzlement on the face of the VP of engineering.
I handed the paper to the VP who asked the dreaded, to my boss, "What's this?"
I responded, "My confirmed instructions from <boss>."
The VP read the email trail, noting the confirmation from my boss with raised eyebrows and he said "Thank you <employee>, you can return to work, I'll deal with this."
I got out reasonably quickly.
Now this particular VP was old school, he didn't shout at people often as one had to work at it to get his dander up... work REALLY hard at it. Apparently, this wasn't the first time this particular manager had gotten caught out as the shouting started as soon as I closed the door.
I never saw my boss again.