This book picks up where Marvel Masterworks: Golden Age Marvel Comics, Vol. 3 or Golden Age Marvel Comics Omnibus, Vol. 1 left off and collects Issues 13-16 of the golden age Marvel Mystery Comics.
The line up of characters is the same throughout all four issues and with one exception, it was the same line up as had been in Marvel Mystery Comics at the end of the previous book. Here are some thoughts:
1) Human Torch: The Human Torch has a great story involving a fire cult in Issues 14 and 15 sandwiched between the Torch fighting Terrorists in Issue 13 and Nazis in a pre-war story in Issue 16. These stories hang together pretty well and there's a great deal of complexity in the fire cult story which actually had some great plot twists in it.
2) Submariner-The Submariner began inching towards the "good guy" category. He fights Nazis in every issue but Issue Issue 15. Unfortunately, in Issue 15, he goes to New York and kidnaps a man and his girlfriend with the intent of forcing her to be his bride. (So not entirely on the side of the angels yet.)
The Submariner stories are connected but that leads to an odd switch. After issue 15, he goes from trying to kidnap the girl and defeat her beau to having them both accompany him to Europe to fight Nazis. Not quite Casablanca, but an interesting shift. In reality, this was setting up the second big Namor-Torch crossover in Marvel Mystery Comics #17 but the breakneck redirection is a little awkward. Also, Namor wears a helmet that looks like its pig shaped in this book. Whenever artists get Namor into wardrobe, things get weird.
That leaves the rest of the book and once again we're left with a mix between the good, the mediocre, and the bad:
On the good side, Ka-zar the Great has a solid plot in Issues 13-15 trying to get back to civilization and rescue his lion brother Zar before meeting a recurring villain back in the Jungle in Issue 16. Terry Vance, School Boy Sleuth continues to provide lighthearted fun with some amazing adventure. My favorite has Terry giving his Dr. Watson, his pet monkey, a gun to guard the bad guys with.
A little less good was the Vision. Not to be confused with the Android of later years, the golden Age Vision was an interdimensional/supersnatural being in stories that were somewhere between Horror and Science Fiction. The stories and art were by Jack Kirby which makes them imaginative and worth reading even if they don't always make sense.
On the down side, the stories featuring the Angel are, if anything, even more boring than prior stories. The stories of Electro the Wonder Robot astonish me only to the degree that they managed to stick around so long. They were simply repetitive and uninteresting.
Bottom Line: It's a decent collection even if a lot of space is wasted. I'm looking forward to Volume 5 and the next meeting of Submariner and the Human Torch.