Rachel thought she had a simple problem. Two employees at her company had complained about unfair treatment. She arranged a meeting with HR, ready to listen and find a solution. What she did not expect was that one afternoon of conversations would uncover something much bigger: management problems across several departments, legal risks from former employees, and a performance review system that had not been checked in four years.
She had, as we say in English, opened a can of worms.
Where does the expression come from?
The phrase has a simple, practical origin. In the past, fishermen stored live worms in small tin cans to use as bait. When you opened the can, the worms would quickly escape — and it was almost impossible to put them all back. From this image, the expression developed its modern meaning.
Today, “to open a can of worms” means to start investigating a problem and unexpectedly discover that it is much more complicated than you thought. The key idea is that, once you start, you cannot easily stop or go back.
“Once you open the can, the worms are already everywhere. There is no putting them back.”
In business, this happens very often. A simple question about costs reveals a problem with suppliers. An investigation into one team exposes a cultural issue across the whole company. A small complaint leads to the discovery of major legal risks. The idiom is so popular because this experience — of finding more than you expected — is extremely common in organisations.
How do Italian speakers say the same thing?
Italian does not have an exact phrase for “can of worms”, but there are several expressions that carry a similar meaning. Each one has a slightly different focus, which makes them interesting to compare.
Notice the difference in focus. The Pandora expression, shared with English, is about things that cannot be undone. The hornet’s nest is about provoking a reaction that was already waiting to happen. Adding fuel to the fire is about poor judgment that makes a bad situation worse. Together, these three expressions cover a similar territory to the English idiom — but from different angles.
This kind of comparison is useful not just for vocabulary, but for understanding how different cultures think about complexity and risk in business.
What does this teach us about business decisions?
Back to Rachel. Her situation raises an important question: should she have looked into the complaints at all? This is the uncomfortable question that the idiom often raises. We usually say “I opened a can of worms” after something goes wrong — as a way of explaining why things became complicated. But the smarter question is to ask it before you act.
There are several things Rachel did well. First, she did not ignore the original complaint. Problems that are ignored tend to grow. What appeared to be a small issue was actually a sign of something much deeper. If she had done nothing, the problems would have returned later — bigger and more expensive to fix.
“A complaint is often just the visible part of a much bigger problem. Treating only the symptom rarely solves anything for long.”
Second, she communicated carefully. When she found new problems, she did not panic and tell everyone everything at once. Instead, she shared information step by step, framing each new discovery as part of a plan to improve the company. This is a key professional skill.
Third, she treated the can of worms as useful information, not just a problem. Companies that never examine their own difficulties tend to build up serious issues over time. The discovery of complexity, while uncomfortable, gives you the chance to fix things properly.
Vocabulary to use in context
The expression “can of worms” belongs to a group of useful phrases for talking about unexpected complexity in business. Here are some connected words and expressions at B1–B2 level:
- To unravel — to slowly discover the full extent of a complicated situation (“As we investigated, the problem began to unravel.”)
- To snowball — to grow quickly and become harder to control (“The complaints snowballed into a major legal issue.”)
- A knock-on effect — a secondary result caused by a primary action (“The management changes had a knock-on effect on staff morale.”)
- To get out of hand — to become impossible to control (“The situation got out of hand very quickly.”)
5. Underlying issue — the real, deeper problem behind what you can see (“The complaints were a sign of an underlying issue with company culture.”)
