The Klingons have been synonymous with Star Trek since the 1960s, but this iconic Klingon weapon did not appear until Star Trek: The Next Generationseason 4. Despite only appearing in seven episodes of Star Trek: The Original Series, the Klingons quickly became one of the show’s most recognizable villains. In the decades since, the Klingons have taken on a life of their own among Trek fans, complete with a fully realized language. Most of the Klingon culture that has become so popular came not from TOS but from TNG and its spin-offs, as well as the original films.