Fragen über die Beispielsätze mit, und die Definition und Benutzung von "Visions"

A: is this a line from a book or a movie?

spring to mind means to come quickly into your mind

A: there's a Christmas poem that mentions visions of Sugar Plum Fairies dancing in their heads. They're referencing that with the phrase with visions of steel toed boots dancing in my head. it means that they wanted to do something and it's not what they are doing so they were imagining what they wanted to do.