Present-day college freshman and devout Christian, Josh Wheaton (Shane Harper), finds his faith challenged on his first day of Philosophy class by the dogmatic and argumentative Professor Radisson (Kevin Sorbo). Radisson begins class by informing students that they will need to disavow, in writing, the existence of God on that first day, or face a failing grade. As other students in the class begin scribbling the words "God Is Dead" on pieces of paper as instructed, Josh find himself at a crossroads, having to choose between his faith and his future. Josh offers a nervous refusal, provoking an irate reaction from his smug professor. Radisson assigns him a daunting task: if Josh will not admit that "God Is Dead," he must prove God's existence by presenting well-researched, intellectual arguments and evidence over the course of the semester, and engage Radisson in a head-to-head debate in front of the class. If Josh fails to convince his classmates of God's existence, he will fail the course and hinder his lofty academic goals. With almost no one in his corner, Josh wonders if he can really fight for what he believes. Can he actually prove the existence of God?