A former film documentarian once steered his students away from making movies about architecture, warning, "Never make a moving picture about things that don't move." The 630-foot tall Gateway Arch might be an exception. It doesn't move muchjust enough on a windy day to spook you out if you're up topbut this new film by Scott Huegerich and Bob Miano affirms that the impossible is possible. Although the documentary places the Arch into historical context, going back to the era of westward expansion, perhaps it's most effective at humanizing designer Eero Saarinen, who came up with the phrase "Gateway to the West." Saarinen's pursuit of "the perfect curve" is compelling stuff. For decades now, the National Park Service has been showing the wonderful Charles Guggenheim documentary Monument to the Dream in the Arch Museum, and that should continue. But Guggenheim focused on the construction of the Arch; this new film puts the story into richer context. Surely the countless visitors to the Arch are entitled to see both.