'Hey Arnold!' might have been a cartoon, but it grappled with some serious issues. During the show's eight-year run on Nickelodeon, Arnold encountered some pretty adult issues.

Complex Original When the last episode of Hey Arnold! aired in 2004, devoted fans were left with many important questions. The cartoon’s mysteries plagued viewers for over a decade.

To people of a particular generation, Hey Arnold! was a constant. The animated TV show was a reliable presence for '90s and early-2000s childhoods due to its accessibility and universal relevance ...