like opening (up) a can of worms

like opening (up) a can of worms

Likely to have complicated, wide-reaching, or unforeseeable results or side effects, especially problematic or negative ones. I worry that trying to alter the existing network setup could be like opening up a can of worms that we're not anticipating. I want to address the issue with the boss, but it's always like opening a can of worms bringing up stuff like that with him.
See also: can, like, of, opening, Worms
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

can of worms, it's a/like opening a

Introducing a complicated problem or unsolvable dilemma. The metaphor alludes to the live bait of fishermen. In a jar or other container, they form an inextricable tangle, wriggling and entwining themselves with one another. The term is American in origin, dating from the mid-twentieth century.
See also: can, like, of, opening
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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