Underbelly

Underbelly is term used to describe the side which is not normally seen. Figuratively it means a vulnerable or weak part, similar to the term Achilles Heel, or alternatively, a hidden, illicit side of society.

This term could refer to:

Business

Underbelly Limited, an entertainment company in the UK
Underbelly (venue), an entertainment venue in the UK

Television
Underbelly (series), an Australian television series
Underbelly, an Australian television drama mini-series, (first in the Underbelly series)
Underbelly: A Tale of Two Cities, an Australian drama mini-series (prequel to Underbelly, second in the Underbelly series)
Underbelly: The Golden Mile, an Australian drama mini-series (sequel to Underbelly: A Tale of Two Cities, prequel to Underbelly, third in the Underbelly series)
Notes from the Underbelly, an American television sitcom