Here's one. Definitely working for a crime family.

You get to hear about one when you're rich enough, because you can't become rich beyond a certain level without being a crook.

Cosby, Trump, Weinstein and the like used fixers to silence victims with a combination of NDAs, intimidation, legal threats, having the national inquirer "buy" the stories and then lock them away, etc

Nearly any executive assistant is a fixer. Fixers are masters of figuring it out and using connections to make things happen.

Fixers exist in every profession and every workplace.

nice try fbi

Fixers are all about connections. If you are rich enough, or politically important, you probably have a fixer. You wronged someone? Your son drove drunk and ran over someone? For the right price your fixer can make the problem disappear. It can be bribe, intimidation, settlement, or in the most extreme case, arrange an unfortunate accident.

I always thought those concierges in fancy hotels act a bit like that. I’ve heard that guests can show up with weird rich person problems and be like “I need three gold Ferraris by 9pm” and the concierges will have to make it happen.

As someone who was briefly involved in that lifestyle, they exist, but it isn't one person you call, it's a network of people you trust that have their own specialties.

Someone check OP's back seat for a dead body

in a non-gangstery/political and more creative industries sense, fixers are also people who for example may know a city or country, who producers can turn to for local knowledge and connections, if the producer doesn't have their own connections that they need to do xxx yy zz