That’s a really tough question!
If I’m going for a film, I’d say Infernal Affairs (无间道). I’ve not seen the Hollywood version, but the Chinese version was one of the first Chinese films that I saw at the cinema and it left an impression.
For TV programs, I could give a list. I’ve got several period dramas that I like watching on the Rakuten Viki app at any one time. The plots are fairly unbelievable - or else ancient China was very dangerous with a lot of murder and intrigue(!) - but the costumes and sets are amazing.