Set in contemporary Japan, an American expatriate finds employment as a bartender at a residential hotel only to discover that it doubles as the base of operations for a major Yakuza syndicate.

see what I'm not getting is that I thought this was perfect..

>>only to discover that it doubles as the base of operations for a major Yakuza syndicate.

And then what? The discovery is an inciting incident. What does he do about what he discovers? In what way does it change his life going forward. For a television show of this genre the logline not only needs to establish the situation but suggest where the story line for the main character is going to go.

Something are assumed, it is assumed contemporary unless stated different. Is it important to state residential bar? What does he want? What threatens him? What is stopping him? Why would he care? It is all in your story. Just not in your line.