APAD: Out of the blue

"Out of the blue" or "out of blue" is an idiom meaning unexpectedly, suddenly, or without any warning, often describing an event or piece of information that appears from nowhere.

As an idiom, out of the blue means completely unforeseen, surprising, or random.

examples :

• After I hadn’t heard from her in six months, she called me out of the blue to meet for lunch.
• I really can't understand how something like this could simply pop up out of the blue.

It can also refer to the 2018 film Out of Blue, a sci-fi noir mystery, or various businesses and creative works with that name t is based on Martin Amis' 1997 novel Night Train. When Detective Mike Hoolihan is called to investigate the shooting of leading astrophysicist and black hole expert, Jennifer Rockwell, she is affected in ways she struggles to comprehend... ...