If you're trying to understand where the new feature "Oz the Great and Powerful" comes in the lengthy mythology of the Emerald City, you'll see when the movie opens Friday that it takes place several years before Dorothy Gale was swept away by a tornado as depicted in the 1939 classic "The Wizard of Oz."

The movie tells the story of how a carnival magician became the Wizard.

There are a lot of similarities between the Judy Garland musical and the new film from director Sam Raimi, including having actors play characters in both the Kansas and Oz worlds.

Michelle Williams plays Glinda. She recalls how floored she was when she finally completely understood the dual casting in the 1939 movie.

"I do remember the feeling I had when I first realized that the characters in her waking life were the same as the characters in her dream life. That the woman on the bicycle was the wicked witch," Williams says.

"I remember being really affected once I had discovered that because I felt kind of like somebody had been playing with me on a subconscious level that I wasn't aware of and that kind of freaked me out as a kid."

Taking on the iconic role of the good with Glinda could have been daunting, but Williams found it easy because of Raimi. She says she always felt comfortable on the set because Raimi had such a positive outlook when he is working.

As for getting to play a witch, the best part of the job to Williams was getting to fly. And, like the Glinda of almost 75 years ago, Williams gets to buzz around the Emerald City in a shimmering bubble.

Follow 'The Following'

Shawn Ashmore is as much in the dark about who is good and who is bad in his new creepy FOX series "The Following" as the audience.

Each week, someone you would least expect turns out to be on the side of the serial killer, who is giving the FBI -- including his old nemesis Ryan Hardy (Kevin Bacon) -- major headaches.

The question of whether his character (Agent Mike Weston) is good or bad comes up while I'm talking to Ashmore about his days playing Iceman in three "X-Men" movies. Even if he knew whether his character is good or bad, he would never tell. The weekly surprises are a big part of what makes the show so fun to watch.

Each surprise also makes it fun for the actors.

"That's what's great about this show. You can't rule anything out," says Ashmore. "As an actor on the show, you constantly have it in the back of your mind. Am I going to die? Am I part of it?

"For me, it's beneficial not to know those things because you never want to wink at the audience. It's not that kind of show. What I like to do is just get the scripts and play that moment.

"I am excited when I get a script to see what's going to happen. I've never read part of one of the scripts and put it down. I've always had to keep reading."

Cumberbatch Q&A

Benedict Cumberbatch ("War Horse") plays Christopher Tietjens, a man dealing with a failing marriage during a time of great unrest in the world, in the five-part HBO series "Parade's End."

I talked to him about making a series set during World War I:

Question: What can you reveal about your character?

Answer: Christopher is a man with a huge heart and empathy for those near to him, and of all position and status and importance in his life, whether it be a wet nurse's, his son who may or may not be his son, his wife, his love of this new woman and his men in war, he's a very generous, big-hearted, sentimental man who Ford describes in the books as being one to cry to a piece of music or art.

How does Christopher compare to playing Sherlock Holmes?

He's very sensitive in comparison to the Sherlock, so there's an emotional depth or resonance that's very different in that regard. Far more sociopathic.

He, like Sherlock, doesn't suffer fools gladly. He carves his way through mediocrity. He's witty and acerbic, and it may not always be an angel, but he's definitely on the side of angels.

He fights a very good fight, in my opinion. He's a heroic character.

This has been a big year for you from "Parade's End" to "Sherlock." How does it feel?

It's been a wonderful year, a wonderful couple of years. It's been extraordinary. Embarrassment of riches is the headline. A real embarrassment of riches.