There’s nothing really outstanding about this issue. The Inhumans are introduced again, and although it makes a narrative sense to introduce them again, it doesn’t make character sense for Crystal to feel the need to get the permission of her people to join the Fantastic Four. Not that it matters because the Baxter Building is quickly invaded by the Alpha Primitives who carry Crystal away.
Pursued by the FF, we find that Maximus the Mad has once again taken control of the Inhuman colony. This event is not shown, but loosely follows on from the events in The Incredible Hulk Super Special #1 (Oct. 1968) which, odd for the time, is not referenced in this issue. He seems to have done it all by ‘hypno’ themed technology — Lockjaw is controlled by a hypno-stud, the wills of the Inhumans are sapped by hypno-potions, and the cliffhanger hinges on what possible destruction Maximus could do with his hypno-gun. The male members of the Inhuman royal family are kept in an impregnable glass box in the throne room. And why not, really?
The male members of the FF in the meantime are caught in a series of rather extraneous and implausible non-fatal traps and pitfalls, which doesn’t do anything to convey character or mood. At one point they run afoul of Zorr, which has to be one of the chattiest lethal robots ever built.
Ultimately, there’s a lot of movement without there really being any action. Nothing more is revealed about the Inhumans than we knew already, and our characters are being pushed into new situations or dynamics.