The Green Hornet started principal photography last week, and thanks to various sources we’ve got photos of stars Seth Rogen, Cameron Diaz, Jay Chou and director Michel Gondry on set, as well as a first look at Jay Chou’s stunt double in character as the Hornet’s sidekick Kato.

The photos come from CrazyCritics.com, SuperHero Hype and JustJared. The first set looks to be pulled from a behind the scenes video, showing Gondry, a dapper Rogen and Diaz hamming it up. In other photos, reproduced below, we see Rogen, Diaz and Chou in character in other scenes, and you can get a good idea of what Kato’s costume looks like from the shots of his stunt double. I like the look — classic Kato, not significantly changed.

The next sets have some possible spoilers, and though we know next to nothing about the Rogen and Evan Goldberg script, making it difficult to put the stuff together out of context, I’d guess that some of you might not want to see anything at all. Click through to the original galleries (here and here) to see all the images.

One of the scenes from which these photos come is an outdoor press conference, at which Seth Rogen’s character is shot in the shoulder. The other shows a the Hornet’s car wrecked, with emergency vehicles nearby.

In addition to Rogen, Diaz and Chou, the film features Edward James Olmos, David Harbour, Tom Wilkinson and (though he’s still in negotiations) Nicolas Cage. The cast and these photos are all we know for sure about the story besides the fact that it will be some sort of update of the character originally created for radio by George W. Trendle and later brought to life on television with Van Williams as the Hornet and a young Bruce Lee as Kato.

The Green Hornet opens on December 17, 2010, opposite stiff competition from Disney’s Tron Legacy.