Students of Giano Middle School, Kayla Arizaga,11, left, and Guadalupe Vera, 12, get under their desks during the Great California ShakeOut earthquake drill. (Eric Reed / Staff Photographer)
The Big One - it's not a matter of "if," Californians have been told. It's a matter of "when."
And "when" came at exactly 10:21 a.m. on Oct. 21, when millions of residents dropped to the ground, covered their heads under a table and held its legs in hopes of preparing themselves for the inevitable - a massive earthquake.