
At best you can say, "Hey, look, my idea
has an INTERNAL logical consistency."
The Big Bang Theory Season 1, Episode 3

Internal jugular.
Money Heist Season 1, Episode 5

I'm plagued by an INTERNAL struggle.
The Big Bang Theory Season 8, Episode 6

According to the head of INTERNAL medicine
Money Heist Season 1, Episode 5

If you want, I can call Internal Affairs,
Money Heist Season 1, Episode 11