I used to work in financial services as a quant. Friend of mine told me about when they were doing a huge arb in the metals markets they needed to do a trade where they took physical delivery of a very very very substantial amount of gold. Like think super villain in a movie doing a heist type of levels. So naturally the team who knew what was going down was kept super small and the details were kept really tight. Morning of the trade my friend goes to get his hair cut. Barber says to him “so I hear you guys took delivery of a bunch of gold”. My friends chin hit the floor.

Turns out one of the security guards came to get his hair cut and was moaning about how tired his arms were from unloading the vans and putting it all in the vault.