diff --git a/src/index.js b/src/index.js
index d83f72e..24a13d3 100644
--- a/src/index.js
+++ b/src/index.js
@@ -152,7 +152,7 @@ export class SlideDeck extends React.Component {
   getMode = () => {
     const { mode } = querystring.parse(window.location.search.replace(/^\?/, ''))
     this.setState({
-      mode: modes[mode]
+      mode: modes[mode] || modes.normal
     })
   }