a light bulb over my head

[Idiomaticus]

I heard the expression “there’s a light bulb over my head” in the movie Working Girl. Can I use it instead of “I have the idea”? I deliberately said the idea instead of an idea because I'm writting a peculiar riddle of mine with pun. Thanks.

 

[I'm With Stupid]

It's not something I've ever heard anyone say in real life, but people would understand what you mean.

 

[Rover_KE]

It's a reference to a cartoon device.

A bright light bulb over a character's head indicates that he/she has had a brilliant idea.

Rover