Bringing a beloved (or at least nostalgia inducing) television show to the big screen is no easy undertaking (especially for shows that have been off the air for a few good years.) The task of adapting existing material (whether it be from a book series, a comic book or a well-known public figure) can be daunting as you hope to live up to expectations while also trying cultivate new fans. When it comes to turning a television show into a film, having a few well placed cameos from the original cast, rooting the film in a story true to that show’s world and (seeing as many of these shows were comedies) not letting the film version take itself too seriously seem to be the keys to these adaptation’s success. With Phil Lord and Chris Miller’s updated 21 Jump Street taking to the silver screen this weekend, I realized that the one thing all these shows have in common (regardless of when they aired, who starred in them or what they were about) is also the one element that many television shows on air today have done away with – a catchy theme song.