Backup: Kirk Cousins

Best-case scenario: Despite suffering what appeared to be a catastrophic knee injury, RGIII makes like Adrian Peterson and triumphantly returns in the season opener. Once under center, he immediately picks up where he left off: confounding NFL defenses with his arm and his legs and confusing women with his braids.
Worst-case scenario: RGIII's knee and reckless style remain a gruesome injury waiting to happen and the first big lick this season puts his career in jeopardy. Slide, Robert. SLIDE!