Best game on SNES is now in Virtual Console.
Story begins right after original Game Boy game Metroid II: Return of Samus, in which heroine Samus Aran tells of how she eradicated metroids from planet SR-388. A metroid larva had hatched from an egg and Samus brings it to the Ceres Space Colony. Scientists then discover that the powers of metroids could be harnessed for the benefit of mankind. Just after Samus has left the Colony she receives a distress call and finds larva missing and scientists dead. In the process Samus escapes the colony when it self-destructs and heads to planet Zebes, which is a Space Pirate base. Now it's up to you as Samus to do lots of exploration, shooting and jumping.
Graphics have aged quite a bit, but it can clearly be seen that Super Metroid has been the foundation on which other 2D Metroids have based their look and gameplay on. Colors are used vividly and overall this looks like an SNES should look.
Sound design especially in music is classic stuff and every Metroid game since Super Metroid has copied these themes and sounds eagerly. Audio effects on shooting and explosions on the other hand are almost exclusively boring and lifeless, but they will not spoil your experience.
Gameplay is 2D action game, where you move from point to point in a non-linear fashion: you have one giant planet to explore and it's full of enemies, power-ups and boss fights.
Super Metroid is a long and elaborate game. You will probably need a walkthrough in order to complete it and remember to dedicate a lot of time to it.
A classic game just like you remember it and even if you don't I recommend you to see one of the best games ever made.