Good Omens had an uphill struggle from the moment it was conceived. I'm obviously a huge fan of Pratchett's writing, very much enjoy Gaiman, and the combination of the two of them in Good Omens made it an instant classic and a firm favourite. I even own a collector's edition of the book. That said, Amazon's adaptation of Gaiman's American Gods left me feeling like it was at least in competent hands, and the casting of Michael Sheen and David Tennant seemed pretty ideal, so my hopes were at least a little raised.
What was delivered is a pretty great attempt. It's no instant classic and there are plenty of things that I would like to see changed, but they're all minor niggles. The broad strokes, the main characters, the overall feel of the show, the dialogue and the acting are all pretty much spot on. The world feels slightly off kilter but recognisable, as any combination of Pratchett and Gaiman should, and they haven't shied away from the weirder areas of humour. Nor have the writers and director felt the need to jam every joke from the page down your throat, to point them out and yell "Look, we included in, love us!" as can be the case when you have such a devoted fanbase. Instead, small gags and fun details, such as the fact that all CDs eventually turn into Queen's Greatest Hits if left in a car for too long, are never explicitly mentioned, but still make an appearance. For fans, these subtle nods will be like Easter Eggs and will reward repeat viewing, whilst for the casual watcher nothing untoward seems to happen.
In other ways, though, the show is a little too in-your-face. Art direction in particular is a strong hit or miss affair, with some elements blending perfectly into the wider world and others standing out jarringly. Probably worst amongst these are Tennants CG eyes. I have no issue with them being CG and they definitely needed to be snake slits, yellow surrounds etc. but they are so vivid in the TV show that they distract from every scene where he isn't wearing shades. A more subtle, actually snake-like form and colouration would have just looked better. Similarly, and probably most annoying, the decision to make scene captions a whole-screen fence post and signage "splash" effect is awful. It weirdly jolted you out of the narrative each time it happened in the first couple of episodes and by the end of the show it had just become a pet hate. It isn't done well enough to look interesting, it's clearly CG, it's never explained or relevant from a design perspective, and it just feels odd. I'm also not sure about the over-the-top glowing red eyes of Adam when he begins to go full Antichrist.
On the other hand, elements like Angel wings, the wider demon community, Tennant's flaming car, the seance scene, Witch-hunter weapons, and the cast's costumes are all fantastic. They're clearly Gaiman inspired, with a similar vibe to American Gods as well as his work on Doctor Who, but it all works well together. From a design perspective, the four horsemen are fine, though I appreciate the literal depths they went to with Death's face, but their motorbikes are amazing. Famine's in particular is just such a clever piece of prop design, being instantly recognisable as his without him in frame.
Plus, and possibly most importantly, they really stuck the landing. I don't know whether I just became more used to the narrative devices and world that the team had built over time, but it definitely felt like the show got better with each episode, culminating in a really excellent finale. I love that the story keeps going after Armageddon and you get to see the two main characters musing around the theology at work directly, but even more so watching Adam become the "embodiment of humanity" was great and extremely well done for such a young actor (actually, all of the kids were fantastic throughout, now I think about it). Equally excellent was both the direction and subtle acting quirks that gave away the big twist, but made it so much more fun for doing so; Sheen and Tennant do such a good job of acting like they're each other acting to be themselves, but also the little bits like taking a taxi, or the subtle inflections in their voice as they enjoy mildly hamming up the other person. It's just great!
Also, the cameos by Benedict Cumberbatch, Johnny Vegas, Andy Hamilton were all excellent and Nick Offerman without a beard is just a little off-putting...
In short, I'm impressed. They got the casting spot on, the adaptation from a dialogue perspective is pretty flawless, and the rest gets carried over the line comfortably as a result. Yes, it could be better, but only marginally and for a TV show it's pretty darn great. If you're a fan of either author, let alone the book, you'll definitely get a kick out of it.