‚ÄčThe 30th anniversary of "Back to the Future" suggests the question: Is director Robert Zemeckis more Marty McFly or more Doc Brown?

Like both characters, he's all about solving puzzles. The characters in his movies almost always have tricky problems that require complex solutions. Like Doc, Zemeckis often finds cutting-edge technical solutions for the special effects challenges of his own storytelling, from the early CGI on "Back to the Future Part II" and "Forrest Gump" to the motion-capture animation of many of his recent films. And like Marty, he finds a way to make those complicated solutions relatable to everyone.

The result has been a four-decade career full of populist blockbusters that also awe critics. Here are the must-see movies that define that career.

"Back to the Future 30th Anniversary Trilogy" is available to own now on Blu-ray & DVD.