The Further Adventures of Beowulf does what it says on the cover. The book starts off with an interesting introduction discussing the legacy of the Beowulf text and Middle-Earth. This is followed by 'The Deeds of Beowulf' translated into prose by John Earle in 1892. This prose version is rather old fashioned (i.e. stuffy and stilted) and has a few issues with sentence structure, which could have used cleaning up and clarification by an editor, or better yet, the inclusion of a better prose (or verse) version or even just a summary of the Beowulf story.
The book then provides 4 fantasy-tales, by 4 different authors, involving the adventures of Beowulf after his run-in with Grendel. These 4 fantasy adventures are written in a style that reminds me of a typical pulpy Sword & Sorcery/ Forgotten Realms Novel, but each short story is rather interesting, or at least entertaining. The 4 further adventures of Beowulf are:
-Beowulf and the City of the Dark elves by Jeff Grubb;
-Beowulf and the Titan by Lynn Abbey;
-Beowulf and the Attack of the Trolls by Wolfgang Baur;
-Beowulf and the Wraith by Ed Greenwood
Each chapter/story is followed by a short (rather pointless and silly) interlude (Beowulf and the master of his Critics) which doesn't fit and could have been left out. The book also includes a rather useful (especially for scholars of Beowulf) "partial, annotated bibliography of the Beowulf cannon" through to current times. This is useful if you want to find other Beowulf stories in text or film.
In short, this is an entertaining, but not spectacular, fantasy anthology featuring the further adventures of Beowulf that could have used improvements with some of the other material.