The phrase "blue murder" is an idiom that means to make a loud or extreme fuss, uproar, or outcry. It is often used to express a situation where someone is expressing strong anger, protest, or complaint about something. Full definition
Can't blame his fans, if we had a player that was shit and lazy with a stupid agent we would all be screaming blue murder on here. (justarsenal.com)
It's a toss of the coin really take a chance with labour who say nothing wrong with the banking bonus culture or the banking crimes or in fact the fat cats MP's who got away with blue murder on expenses. (leftfutures.org)
«Don't worry,» said the midwife, as I trembled at the sound of a woman screaming blue murder in the room next door. (faith.org.uk)