To start with, this is an anime that gives off an oldschool-ish feeling and that is to be expected, since the manga started publishing about 40 years ago. The drawing style clearly shows it: all characters have very serious and rough faces, showing each and every wrinkle. The scenery is quite good. Even though it might lack detail, it clearly isn't the type you would shove off as a picture-based-and-streched-over-the-horizon background.
There are no major problems with the sound either. At first it might feel as if there is a lack of music, but as the series goes on, you will probably start to notice the recurring tones. Some might find them a tad repetitive, but considering the retro feeling this anime gives off, some repetitiveness could actually be considered as a tool to emphasize that special kind of feel. I have no complaints about the opening themes or the ending themes either.
When it comes to the characters, it is quite difficult to provide an evaluation. As this show is centered on Duke Tougou (a.k.a. Golgo 13) going on solo assignments, you will not be seeing any other major characters. There is not much to say about character development either. I mean, we have a cold-blooded sniper with nearly inhumane skills, unwavering principles and, most of the time, a perfect example of a poker face. He is certainly the most silent protagonist I have ever seen and we can't "hear" his thoughts either, so what is there to develop (not to mention how)? Still, it feels like Golgo becomes a tad more talkative and expressive towards the end of the series, so it is possible to interpret it as a slight emotional shift, though the reason for it is anyone's guess. Despite this, though, all the characters feel quite real and alive; they all have individual personalities and different attitudes towards Golgo, so the anime does not lose ground on this aspect either.
Where it does, though, is the story. Or, more precisely, the lack thereof. The series is episodic and there is no relation between the assignments whatsoever. In fact, if your younger sibling wanted to make a prank and rearranged the playlist while you were making a sandwich, you would not even notice it. I am guessing the studio picked the missions from the manga randomly, hence the lack of cohesion. Yet, despite the anime not having a coherent plot as a whole, every episode has a different and unique story, various circumstances and characters that continue to pique the viewers interest and provide tons of entertainment.
To conclude, anime series with no plot tend to lose their appeal very quickly. However, Golgo 13 is quite enjoyable. It just has something in it that makes you look forward to Tougou's next assignment and keeps you wondering, just how he is going to demonstrate his prowess. When his enemies underestimate him or make wrong deductions, you just get the proud feeling "That's my Golgo! Those bastards don't have a chance! Show them who's boss!", or something along those lines.
If you are a fan of super-manliness, protagonists having nearly inhumane skills and an oldschool feel wrapping it all up, this is one show you should definitely watch.
