A bit of necessary preamble: in Inferno, the science fiction writer Carpenter falls from a window during a drinking stunt and wakes up in what resembles the Vestibule of Hell as depicted by Dante. Initially sceptical, he dubs the place Infernoland, and struggles to rationalise it in SF terms. But finally, convinced by physical impossibilities such as regeneration from mortal injuries, he accepts its reality as Dante's Hell. Although puzzled by some aspects (for instance, how he mostly meets Americans, just as Dante mostly met Italians) he concludes that Hell is a kind of theological last chance. Hell is escapable, but only for those with the resolve to journey to its centre. He undertakes this quest, guided by a reformed Benito Mussolini in a Virgil-like role, and accompanied by Jerome Corbett, a pilot who died in a Space Shuttle accident, and William Bonney (i.e. Billy the Kid). Hell's geography is more or less as described by Dante, but with elaborations due to new forms of sin, such as industrial pollution, overtaking archaic ones such as simony.
Escape from Hell initally finds Carpenter despondent in the Wood of Suicides, telling his story to the tree that is Sylvia Plath. Near the centre of Hell, he had been seized by a bearded man who exploded, and found himself reconstituted back in the Vestibule, where undecided souls chase banners for eternity. Adopting Mussolini's role as a guide, he persuaded a lawyer, Rosemary Bennett, to follow him in retracing the journey to escape, but now he has lost her.
Carpenter finds Hell considerably more complex than he had understood at the end of Inferno. He is not alone among damned souls allowed to wander free in Hell - a role gained, it seems, by virtuous acts and altruism such as freeing trapped souls - and Hell itself is changing. Because Hell must mirror Catholic doctrine, Vatican II has changed the status of many past sinners, and Hell's bureaucracy is struggling to keep up. Hence another way of gaining leniency, and even power, is to be recruited to Hell's infrastructure (whether as simple guards, or in helping to computerise records in Dis, Hell's adminsitrative centre).
Norman Spinrad described Inferno as "the ultimate Sam Peckinpah movie with all the matter-of-fact solidity of a Hal Clement novel ... lunacy of a transcendent order". Escape from Hell came across as less striking and slower-paced, now that I know the scenario, but it makes up in general character-building and historical interest. Niven and Pournelle focus, for instance, on the Hughes-Plath relationship, the motivation of Robert Oppenheimer, and indictment of various forms of US political corruption relating to 9/11 and Hurricane Katrina. The focus on US contemporary persons makes for a slight impediment to reading - I needed to keep a bookmark at the glossary of names - but it was overall a very enjoyable sequel.
On the subject of Dante, reviews are coming out for the Dante's Inferno videogame. There seems general agreement that it's spectacular. But as The Independent said - see Hit & Run: Abandon all hope, it's Dante's Inferno: the game - Dante was an intellectual type not really fitted to the genre:
Dante has been beefed up into a blood-hungry crusader, and the date has been rewound by 100 years. The problem for the developers is that Dante paints himself as a man constantly on the verge of passing out in fear of what confronts him. He doesn't, at least in the version I studied, kick open the gates of Hell and invite the evil dead to bring it on. Yet the poet painted a vast and terrifying landscape in the Divine Comedy, with miserable souls facing punishments that still sear the imagination. And the developers have realised this terrain with great relish – it's hard not to be swept up by the sheer scale and gory glory of the game.
I'm not terribly into that style of game (I wouldn't know an Xbox 360 if it bit me) but its polish and detail - many Dante characters are featured - is certainly an indication of the enduring power of Dante's vision. See the official site. Perhaps, as Inferno did, it'll spark a further renewal of interest in the original.
See also: 1935 ante's Inferno.