"After the first one worked out pretty good, we were pretty much doing the press tour talking about things we would like to improve, other directions we could go, blah blah blah. And then there's the reality of doing it," Downey told reporters in Los Angeles recently while promoting "Sherlock Holmes: A Game of Shadows."
"Anybody who's ever been involved in making the second part to a first that worked, there should be a whole online support team for this. We happened through it," explained the 47-year-old New York native. "There's so much to learn. The greatest disguise [we donned for the detective movie] was us disguising ourselves as consummate by-the-numbers professionals when we're all kind of incredibly eccentric and Warner Bros. has given us the opportunity to do something that is complicated and needs to tick a lot of boxes."
Asked if he gets along as well with any man in real life as his sleuth character Holmes does with Law's Dr. Watson, Downey admitted, "Well, Jude and I are pretty close, but Guy and I are practically brothers, which makes things really interesting.
"There have been times when I've wanted to lop off his head with a machete, but it's just because I love you so much," Downey joked with Ritchie, who was sitting beside him at the press conference. "You know what I mean? There's no one you love more really, is there?"
Although the actors were given the freedom to ad-lib, Downey emphasized how everything starts with a really great script.
"I think the goal is to make a well-written scene seem like it's improvised," the actor said. "Or to come up with things that you find in the room that you couldn't have known until you get into the real situation and try to improve as you go along."
The star of "Weird Science," "Less Than Zero," "Natural Born Killers," "Chaplin," "Kiss Kiss Bang Bang," "Good Night and Good Luck," "Tropic Thunder" and "Iron Man" said he got a kick out of dressing in drag when Holmes donned a disguise in "Game of Shadows."
"I put on some makeup," he recalled. "I thought I looked like Arnold Schwarzenegger's dwarf brother. That's what I thought I looked like. And the lead singer from The Cure. Robert Smith."
He said rumors claiming he and Law plan to star in a remake of "Some Like it Hot," a movie about two male musicians who dress as women to escape gangsters, are wildly exaggerated.
"The Mrs. referenced that a while ago," Downey said of his film producer wife, Susan. "That's what it reminded her of."
Questioned about working with Harris, who plays Holmes' sworn enemy Moriarty in the film, Downey offers nothing but praise, especially when he spoke of how well Harris adapted when the screenplay evolved or schedule changed.
"He would come in and we'd have a scene that he's shooting in two days and he'd be like, 'Is this going to pretty much stay like this?' I was like, 'Not a word of it.' 'Can I have something that I can study the night before?' I was like, 'I'm going to venture a no on the possibility of yes.' And it would be like that and the stakes were so high in every scene and then there were complicated camera shots, so it was pretty terrifying," Downey confessed. "Jared kept pushing toward… it wasn't personal. It wasn't like, 'I don't want to be embarrassed, I want to do a good job and I want to come off great and I want great dialogue.' It was more like it kept coming back to this great archetype he was trying to represent. …
"Everything Jared did in the course of making this movie was essentially thrown at him with very little time to prepare and also talked about a lot philosophically as opposed to actually getting ready to do it in a professional way, so it was shock and awe. … And he was really quite nice. Once in a while he would say: 'I really just beg of you, if I could even have a semblance of knowing what I might say, I guarantee you I could do a better job with it because I wouldn't be like you, Robert, for this long scene that you just wrote wearing an earwig where someone's telling you what to say in the other room. I would actually know what I was going to say.' I'd be like, 'Interesting, yeah, everyone has their own process.'
"Guy told him to go home and he wanted him to come back singing a German aria the next day. Nobody learns a German aria overnight, except Jared Harris," Downey joked about his co-star.
"Sherlock Holmes: A Game of Shadows" was released on DVD and Blu-ray Tuesday.
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