In 1888, notorious serial killer Jack The Ripper allegedly sent Scotland Yard a letter, with the return address of "from Hell", and that's how From Hell gets it's title.
Very, very loosely based on fact, From Hell gives us a rather outlandish theory on the Ripper mystery, in a lurid, bloody way.

Johnny Depp stars as a Police Inspector assigned to the Ripper case. I don't give away anything about the movies I see, so I can't really say much about his character without at least teasing to a spoiler, so I'll just say that as usual, Depp's acting is great, even if he's been better in the past. I thought his performance as Ichabod Crane in SLEEPY HOLLOW was much more interesting and entertaining. But despite similar eras in history, the two films really can't be compared too much.
I will credit Depp with his accent though.
I'm not sure exactly what the dialect was, but at least he was consistent.

Heather Graham plays one of the prostitutes that could end up on the wrong end of The Ripper's blade. I wasn't crazy about her being cast in this film, and to be honest, after seeing the film, I'm kind of indifferent to it. She wasn't bad, but she didn't blow me away either. Still, like Depp, at least she was consistent with her accent.

From Hell is directed by gritty "urban film" directors, The Hughes brothers. They did a pretty great job here with the look of the film. Dark, dreary and creepy, with a gothic look at times reminiscent of Coppola's Bram Stoker's Dracula and Burton's Sleepy Hollow.
Also, being that their previous films are urban dramas, this is a nice change of pace and shows great range on their part.
I also think they did a good job of limiting the onscreen carnage, though plenty does still make it to the screen. The real Jack The Ripper really did commit atrocities, but this film didn't really need to show them too explicitly to get the point across.

From Hell is based on the graphic novel of the same name by Alan Moore and Eddie Campbell.
(A graphic novel is, in it's simplest definition, a glorified comic book…though as a comic book fan, I know it's much more than that…)
Alan Moore is a very well respected writer I the comic book industry, and authored one of the most acclaimed comic books of all time, Watchmen. That story has been long since optioned for film, but I'm not sure if it'll ever come to fruition, or what, if any, Moore's involvement will be in that.
I've read that his take on the Ripper case is very liberal in and of itself, while the screenplay of the movie itself, not by Moore, takes plenty of liberties with the graphic novel, so who knows what's what.

I'm not sure I enjoyed From Hell.
It's visually interesting, but maybe a little too farfetched.
But it is bloody, disturbing, and it does make an impression, and maybe that's all it has to do…