The nice thing about a show being on the air for a long while is that the creators can reach back and dust off an underutilized character for another go-round.
If the character is still living, that is. And that isn't necessarily a deal-breaker.
On Hawaii Five-0 Season 7 Episode 20, the blast from the past was Harry Brown.
First introduced on Hawaii Five-0 Season 5 Episode 10, Harry was a retired Honolulu policeman turned PI and an old friend of McGarrett's dad Jack.
Harry was a welcome breath of nicotine-polluted air and came from the wise-cracking gumshoe tradition.
He literally brought the case of the week to McGarrett, and it was a good twisty, turny one.
A selfish rich man hired Harry to follow his wife, who got kidnapped right in front of Harry. His attempt to intercede didn't go well, which was why he ended up at Five-0 headquarters, getting his head stitched up.
Five-0 got there too late to monitor the first ransom demand, which the rich guy ignored. After all, it was only his wife. It wasn't until the kidnappers tried again by kidnapping his mistress that he took them seriously.
Harry was right to punch him.
The kidnappers had a fairly well thought-out plan, especially once Harry figured out that Celine the wife was actually the brains behind the job.
She had to be, as one kidnapper got shot dead, while the other got picked up bleeding at the airport. Did he really think that was going to work?
This episode was a little light on the action tonight. But maybe that's to be expected when the primary guest star is a retired cop.
The explosive-vest scene was almost tension-free. The kidnappers got waved along, only to quickly escape. And Celine the hostage got quickly freed from the vest.
The ransom-delivery scene was more exciting, with the zip-line a clever way to make the payment. Why, after they got the money, the kidnappers hung around long enough for one of them to get shot, I don't know.
Maybe it was because Chin had the magical ability to get off the elevator just at the right time to fire at the second kidnapper. Take the stairs next time, dude! No, that didn't work, because Danny was there to wing him.
Then Danny blindly followed the second kidnapper down the laundry chute, so naturally, he got knocked out.
The two kidnappers weren't the sharpest pencils in the box, but Five-0 and Harry spent much of the hours reacting, not acting.
Beyond his eventually solving the case, the best part about Harry's appearance was his interactions with the Five-0 team, trying to make sense of Jerry, offering relationship advice to Danny ("Haircut") and generally imposing his worldview on anyone who would listen.
Grover was almost a wallflower in comparison, no mean feat.
Think Harry could go into the rotation with Jerry, Noelani, Kamekona, Eric and the significant others (or it that too crowded already)? OK, maybe once a season. It's a great way to honor TV's cop-show past.
Now the other big news: Rachel is getting divorced and Danny could conceivably put his family back together again. All he has to do is break up with Melissa. Or just keep being Danny and that will take care of itself.
I love how Harry, three ex-wives and all, felt entitled to offer guidance to Danny (and rolled his eyes at the idea of cops undergoing therapy). His advice wasn't necessarily on point, but it was good to have another voice in the Danny-McGarrett debates.
So how does mumbling Danny explain to Grace that he and her mother just aren't in the same head space anymore? That should be fun. He can be profound in the car, but no so much elsewhere.
With Harry using up most of the air, there wasn't much space for the other supporting characters. Noelani did make the most of her couple of scenes, however. I miss Max, but I sense she'll be an able replacement.
Yakuza boss Michelle Shioma, last seen in Hawaii Five-0 Season 6 Episode 25, returns on Hawaii Five-0 Season 7 Episode 21, and it looks like the whole squad is in trouble. This might be a good time to bring back Adam as well.
To refresh yourself about Shioma, watch Hawaii Five-0 online.
How did you enjoy Harry's return? Did the case itself have enough going on? Rachel or Melissa for Danny? Comment below.
Dale McGarrigle is a staff writer for TV Fanatic. Follow him on Twitter.