Yesterday was the twentieth anniversary of the Spider-Man premiere episode "Night of the Lizard". The episode remains one of the best reviewed of the series, and ranks highly among many Marvel animated premieres. Created to showcase the potential of the series, it features noticeably superior animation compared to the rest of the series.
In the episode, Spider-Man discovers that his friend and mentor Dr. Curt Connors has transformed into the Lizard. He must cure the professor before the over-ambitious Eddie Brock can uncover proof of the transformation exposing him in The Daily Bugle.
The series went on to become one of the most beloved animated superhero shows. It eventually reached five seasons and sixty-five episodes making it the second longest running Marvel animated series ever, behind only its counterpart X-Men.