When physicist Xan Keller's CERN experiment goes spectacularly wrong, he finds himself stranded in the Stone Age where his particle physics PhD is about as helpful as a screen door on a submarine. Suddenly the guy who manipulated subatomic particles has to learn how to make fire without burning himself alive, hunt without becoming the hunted, and navigate tribal politics that make academic conferences look like kindergarten playtime. But as Xan journeys through this prehistoric world toward ancient Mycenae, he discovers that being stuck in the past isn't just about survival-it's about mysterious symbols that shouldn't exist, a tribe that knows more than they're saying, and the terrifying possibility that his "accident" was anything but random. Now he's caught between two impossible choices: find a way back to his modern life or stay in this brutal, beautiful world where every decision could reshape the entire timeline, and where he's finally learning what it means to be truly human.