The evil Dr. N. Cortex has small plans for the world - he's shrunk the entire world into the size of a grapefruit and it's up to Crash to traverse 20 levels in order to collect enough crystals to return the world back into its normal size.
This is essentially four games in one. Each of the four worlds is split up into five levels and a boss fight. Each of the five worlds is either a traditional side-scroller, a side-scrolling scuba mission, a Yeti-chase similar to the traditional Crash games, or a Starfox style shooter.
Although Crash can be completed in about four hours; there is plenty to unlock in the game. In fact, if you plan on fighting the final boss and the 'true' ending - plan on spending a lot of time on the game.