Here's a movie trivia question for you: Which Robert Downey Jr. character is a brilliant-but-flawed vigilante with wit as quick as his right fist? That's easy! Sherlock Holmes... or is it Iron Man? Although the two inhabit completely different worlds -- Victorian England and Malibu, California respectively -- these guys have so much in common you might mistake one as the other in period drag. Which begs the question: How do you like your Downey? With superhero accessories or sleuthing with Watson on his side?