Many of the best Power Rangers made appearances long after their departures from the series, while others never appeared ...

though — Power Rangers Super Megaforce, the 21st season of the franchise that debuted in 1993, premieres Feb. 15 (noon ET/PT) on Nickelodeon.

What happens behind these walls will change everything.

Power Rangers Megaforce debuted on the franchise's twentieth anniversary and presents a new beginning for the Rangers as a whole while looking back on some of the best iterations in Power Rangers ...