When you get to the first Octopus, punch out the tentacles or buy the TALCUM POWDER and become invincible then punch him in the face twice. Next put Alex's stomach on the chest and move left and right while holding Down on the d-pad until you go underground to a BONUS ROUND.
Continue
When the words "Game Over" appear on the screen, hold Up and press Button 2 eight times. This will enable you to continue, but only if you have $400 or more.