iD 2020.01: The World's Unsolved Mysteries
iD 2019.11: What Makes Me Younger? What Makes Me Older?
iD 2019.09: The Greatest Legends of All Time
iD 2019.07: What Happens When We See Red?
iD 2019.05: Could You Stay Alive?
iD 2019.03: 33 Things that Program your Brain to Make You Fat, Weak, and Sick
iD 2019.01: The Butterfly Effect in History
iD 2018.11: The Secret Power of Words
iD 2018.09: 100 Facts You Need to Know about your Body
iD 2018.07: The World's Weirdest Places
iD 2018.05: Assert Yourself!
iD 2018.03: 30 Assassinations that Made History
iD 2018.01: What are you afraid of?
iD 2017.11: What's It Gonna Be?
iD 2017.09: The Biggest Traitors of World History
iD 2017.07: Always Tired?
iD 2017.05: The Surprising Power of Thoughts
iD 2017.03: Solving the Greatest Mysteries of World History
iD 2017.02: What if Hitler had been Assassinated?
iD 2016.12: Why it pays to be a psychopath