simply put, this is the best mario flash ever. if you have time understanding the narrator, I shall provide his scholarly monolog in text form:
'BOWSER from his CASTLE! ONE day Bowser was just Walking down the street, because he was from his castle. and mario was like "hey bowser (???) CRASHLE", and luigi's like "Yeah" (???) because MARIO ate the mushroom to save the princess, but she was in another castle. and then Bowser was in a castle, but it wasnt really bowser, and then Bowser was from his Castle. then Mario went into his castle and died, then he came back and he died, then he came back and got the thing and Bowser died. and then the princess wasnt the princess and she was in another castle. but it still wasnt bowser, and it still wasnt the princess, and he never found her.'
basically, it's a monolog detailing the plot of the original "Super Mario" game. Best Mario Flash Ever.