To appreciate the Redshirts book, readers need to be familiar with the Redshirts trope. This is basically the good guy equivalent of Stormtroopers in fiction. The inefficient mooks who act as cannon fodder while the main characters do stuff. Whereas Stormtroopers are jokingly known for missing every shot, Red Shirts are known for dying easily and instantly. Mainly to serve as a warning sign so the protagonists know what to avoid. Anyone who is at least somewhat familiar with Star Trek should be familiar with this concept. And with the hilarious ways Redshirts pays homage to the trope.
If you have never seen Star Trek before reading this book, go watch a few episodes beforehand. Any episodes, it really does not matter which ones. But preferably episodes of the Original Series or Next Generation. Even being familiar with the general hokeyness of 1960s television (compared to modern shows) helps here. This was an era where science fiction was a lot less “science” and a lot more “fiction”. Redshirts essentially takes those crazy concepts and tries to make them more real. Think of any episode of Star Trek and ask, “How would a real, living, breathing person react to these shenanigans?”
This all makes for a very different book than Scalzi’s main claim to fame, Old Man’s War. Both books are sci-fi, but Old Man’s War is an action story while Redshirts is a comedy. My only complaint about this book is that the page count is a bit deceptive. The last 20-25% or so of the book features a few short stories that wrap up unresolved plot points from the main story. It is nice to have that closure, but it means the meat of the book is only a bit over the 200-page mark, not the 300-page mark. Still, the main story did not really need to be any longer, so it all worked out in the end.
Even if you are not a diehard Star Trek fan (which I, myself, am not) this is still a fun book. I enjoyed it a lot, so much so I may actually go take a crack at watching Star Trek sometime. Is this an overall great work of literature? No. Is it great at what it sets out to do? Oh yes, definitely. If you need to fill an afternoon with some laughs, Redshirts is a great way to do it.