Quite a versatile product, this work caters for both those who wish to take the unusual role of divinity by playing a demigod as a character as well as for DMs who want to have the odd demigod wandering around his world and, no doubt, causing trouble!
Demigods are the offspring of a deity and a mortal, and have some of the features of both. Such a union can happen by chance (at least on the mortal's part) or as part of a deliberate ritual, but the majority of demigods thus produced often find it hard to settle as there's always a bit of 'otherness' about them even if they have never been acknowledged by their divine parent, even if they do not know who it is or even what they are. Still, great heroes and great villains have arisen from such origins. Many who do know of their ancestry choose to become clerics or paladins devoted to their divine parent... and some (there's a feat for it) are even able to parent more demigods in their turn.
All the appropriate detail is provided for those wishing to use the demigod as a character race, complete with apposite powers to choose from - some relating to general divinity and some drawing on the particular deity involved. If that doesn't suit, futher notes are provided for those who would prefer to present demigods as monsters. The whole thing rounds out with some adventure ideas, as well as blank power cards, a character sheet and some rather generic counters.
It is an interesting concept, and one which has spawned many myths and legends... but I feel that it needs to be approached with caution, lest a demigod PC end up dominating the plot and leaving the rest of the party as hangers-on rather than heroes in their own right. Carefully handled, though, it could make for some powerful and interesting adventures.
[4 of 5 Stars!]