Both feature handsome swashbuckling cowboy James West and his scientific assistant Artemus Gordon, who act as secret agents for the Federal government in the post-Civil War frontier. Both feature a slightly strange old-timey science-fiction tone, and a fiendish supervillain.
The big difference comes from casting - instead of Robert Conrad, Will Smith plays James West. Since we like Will Smith, we have no problem with that. His West is still cocky and quick on the draw, but maybe a little more sarcastic. The movie doesn't ignore his race, using as a gag (comic lynching?) and dramatic motivation (the villain is an unreformed Confederate).
Which brings us to the villain. In the 1965 series, Dr. Miguelito Loveless, played by dwarf actor Michael Dunn, was brilliantly evil. In the 1999 movie, Dr. Arliss Loveless is played by Kenneth Branagh, with a hammy southern accent and a steam powered wheelchair.
Which brings up the key to this whole review: Steampunk. "Steampunk" is a science fiction genre featuring advanced technology based on steam, brass, walnut paneling and lovely Victorian ornamentation. Wild Wild West is totally steampunk. It's not a spoiler to mention the single most important thing about this film: 80-ft tall mechanical spider.
I have to mention the consensus view of this movie - that it is not very good. We say:
- Will Smith as Jim West, Kevin Klein as Artemus Gordon, Kenneth Branagh: Good
- Salma Hayek in a throw-away role: Lame (but not bad). A big step down from Bandidas
- Will Smith's stream of cripple jokes aimed at Dr. Legless (see, I did it too): Appalling (but kind of funny)
- The action, stunts, etc: Average or better
- 80-ft tall brass and steel steam driven mechanical spider!