Notice the unnoticeable! Weird facts about things that are clear and invisible. Learn about the secretive clear cola that came decades before Crystal Pepsi. We've all probably tried the ol' lemon juice invisible ink before, but can it help you outsmart and rob banks? "Before & After" hidden word game, and can you see right through Karen's crystal clear quiz? And yes, there is a real John Cena cameo in this episode. For advertising inquiries, please contact [email protected]! Learn more about your ad choices. Visit megaphone.fm/adchoices