A situtation of unforeseen problems.
Taking that girl home turned out to be a can of worms.
1. A complicated situation.
That would open up a whole can of worms!
A prolific source of troubles.
see also: Pandora's Box
Joe really opened a can of worms when he snitched on Leon.
an intertwined set of problems
A virus like that can really open up a can of worms.
A tricky highway location in Rochester, NY where 490 West, 590 North and 590 South all split at the same time. Requires precise manuevering and quick thinking.
"This is News Chopper 10 reporting your morning traffic. We have a 10 car pile up at the can of worms this morning."
A tricky situation which requires much effort to resolve.
My girlfriend caught me kissing another woman, so I think I opened up a can of worms on that one.
Getting into a whole lot of trouble you didn't ask for.
Man, when you went out with that girl, you were opening up one big can of worms.