Tune in to this week's edition of CMT Hot 20 Countdown as we catch up with Thompson Square. The award-winning duo drops by to perform their emotional single, "If I Didn't Have You." Plus, the guys of Florida Georgia Line pay us a visit to talk about their new video, "Get Your Shine On," along with their ACM nominations. Then Katie Cook catches up with Kenny Chesney as he kicks off his No Shoes Nation tour. And in honor of April Fool's Day, we'll tell you about hilarious pranks your favorite stars have played over the years.