Tonight, CBS aired S04E12, "Nine, Ten -- You're Dead".

The episode concerns an attack on an up and coming boxer Robby Davis (Henry Porter) by Willy Stone (Moses Gunn), himself a washed-up boxer suffering from what is now known as CTE due to multiple blows to his head over the years. He smashes Robby's hand, thus ending the young man's career and saving Robby from the same fate Willy suffers. There's only one problem: organized crime has a huge interest in Robby and soon Matty Edmonds (Albert Paulsen) shows up.

Edmonds is not happy one bit with Robby's prognosis and wants the man responsible killed - head on a platter and all. Edmonds even calls back to his home base of Detroit to put a hit on Willy.

In the meantime, McGarrett and crew are trying to stay one step ahead of Edmonds and find Willy to keep him safe. In the end, the hit man Duke (Frank Webb) turns on Edmonds explaining Detroit felt Edmonds lost his marbles calling a hit on Willy. He's apprehended by Five-O and Willy is taken in by the team to someplace safe.

Mr. Mike has a great review on the episode here:

There's a lot to like about this episode even though this isn't exactly my cup of tea, I enjoyed it immensely. We get a peek on Five-O's local contacts and how they interact with the populace. McGarrett's connection to Mae (Lynn Hamilton) and how she's hiding Willy in the basement of her bar. I also enjoyed Danno and Chin's interaction with Mama (Mama Luna) in her deli after she gave Willy food.

This is perhaps one of the best episodes of the series - a strong effort from script to execution. It's classic Five-O!

Happy 50th, "Nine, Ten -- You're Dead"!!!