I have seen this film three times, and each time the adventure has been greater. The cinematography, the sound effects, the many plots importuning on each other, the music and the splendid photography makes this a great film in spite of all, in spite of a poor script that really can't handle all the very different characters and the conflicting plots, that most of them founder on the way, the most objectionable being that of Brian Keith's inability to keep in control in his addiction to laudanum, while Maximilian Schell as the captain makes a magnificent performance, together with John Leyton as the one scientist on board knowing what is going on, Sal Mineo as the son of Rossano Brazzi, the wonderful diving ladies ( - why do they ultimately choose to follow Keith and his lady ashore instead of staying on board with the captain? This is one thing that does not make sense, as also the revolt and sacrifice of the chain gang.) Fortunately there is aslways the vulcano to return to as the main attraction of the plot, and ultimately the vulcano wins. It happened for real, and this was the first of the great catastrophe films later of the 70s that set the standard.