This American Life
Go back to where it all began with Serial's parent podcast, This American Life. The award-winning show is one of the most popular in the country, and for good reason. Each week, host Ira Glass announces a theme and reporters tell a variety of different stories that pertain to it. The topics can range from animal sacrifice to middle school, and often the show will be dedicated to telling just one story in its entirety. I recommend starting with an old episode called "House on Loon Lake." It's dramatic and filled with mystery, just like Serial.