How the mighty have fallen!

As the third season of Game of Thrones begins on Sunday, some of the most ambitious men in HBO's feudal fugue have been laid low.

The dashing and dastardly knight Jaime Lannister (Nikolaj Coster-Waldau) has been kept chained in a livestock cage for most of a year; Stannis Baratheon (Stephen Dillane) suffered a devastating defeat at the Battle of Blackwater Bay. Even Tyrion (Emmy winner Peter Dinklage) has been stripped of his title as Hand of the King and now licks his disfiguring wounds in a cramped cell.

And that's just the tip of the lance. It would take this entire article to summarize the profusion of plotlines in the mythical realm of Westeros.

Game of Thrones, adapted from George R.R. Martin's fictional fantasy series A Song of Ice and Fire, plays out on a scale that would humble Cecil B. DeMille. This season it will continue to add more major characters (played by actors such as Ciarán Hinds and Diana Rigg) to its massive cast. It all adds up to one of the most intriguing, and demanding, shows in TV history.

"As viewers, we have to become more invested in what's going on," says Paul Booth, an assistant professor of media and cinema studies at DePaul University. "You can't half-watch Game of Thrones."

Perhaps that level of commitment explains why fans are so pumped for the season to begin.

"This is the most excited I can remember being for a TV show since The Sopranos' finale," writes Jeff Kenney of Phoenixville by e-mail. "I picked up some of the just-released Iron Throne beer for the premiere."

Laurie Falcone of Marlton is eager to resume her Game of Thrones viewing ritual. "My husband doesn't watch the show (don't get me started)," she writes in an e-mail. "So when he goes upstairs I will turn off all the lights and sit about two feet from the screen on Sunday."

"So many people come up to me and say, 'I can't freakin' wait,' " says Michael Lombardo, HBO president of programming. " . . . [W]e're experiencing a level of engagement with Game of Thrones that doesn't happen all the time."

The series, steadily growing in popularity, is projected to expand again this season because of robust Blu-ray sales, social media buzz, and enthusiastic word of mouth. June's season finale was watched by 4.2 million people during its scheduled time period and drew 11.6 million across all platforms (including DVRs and HBO Go).

Of course it isn't just the size of the cast or the multiplicity of the plotlines that have viewers enraptured.

Martin, the books' gnomic author, liberally flavored his swords-and-saucery saga with showbiz's most dependable spices: sex and violence. The executive producers of the TV series, David Benioff and Dan Weiss, apparently decided it was still too bland.

"They amped up the sex because it was on HBO," says assistant professor Donald Riggs, who taught an honors colloquium at Drexel University last summer comparing the show's first season to its source material.

"Not that there isn't sexuality in the book, but it's much more explicit on television," he says. "And also the violence - in the book the reader can gloss over it as he or she likes, but on television the brutality is right in your face."

This is no fairy tale. It's a dark, cruel world rife with incest, sadism, castration, and torture. And the casual matter-of-factness with which the TV series treats these elements of depravity is, in an odd way, part of its appeal.

"I loved the Lord of the Rings movies," writes Phoenixville's Kenney, "but I didn't like that they were so clear-cut good vs. evil and targeted at a younger audience. I love that in Game of Thrones it isn't always clear who you should be rooting for and that pretty much anyone can be killed off at any time. It's clearly intended for adults."

A word that is used again and again in praise of the show is maturity.

"Game of Thrones doesn't pander to its audience," says DePaul's Booth. "In a world of reality TV and schlocky sitcoms, it's refreshing to see something mature and adult on television."

Certainly heroes are hard to find in the Seven Kingdoms of Westeros. The most noble characters are capable of shocking savagery, while the most villainous may display unexpected flashes of compassion or loyalty.

There's certainly no denying that the show is gorgeous to look at. "Frame by frame, it's as textured, as richly detailed, and as well produced as any Hollywood blockbuster," Lombardo brags.

Season 3 was shot on location in Morocco, Northern Ireland, Croatia, and Iceland. The far-flung settings as well as the fact that many of the plotlines never intersect have created a curiously insular experience for the cast.

"It's weird," says Coster-Waldau on the phone. The Danish actor plays "the Kingslayer" Jaime Lannister. "Last week, HBO arranged a big premiere event for Season 3 in Los Angeles and everyone was flying in from all over the world.

"We had a dinner. It was the first time I had ever met a lot of the cast," he continues. "You look at this enormous cast and the reality is I'm working with very few actors. It's like a little chamber piece."

A gigantic cast, exotic settings - all this comes at a price. The figure of $50 million has been bandied about for this season.

Yet Lombardo insists that Game of Thrones is "financially successful" because it is a big hit in foreign markets and because DVD sales have broken all of HBO's previous records.

Can you come to the show cold on Sunday? Yes, as long as you have patience. Game of Thrones' canvas is so expansive and populated, it will take time to get oriented. But don't feel bad - it can be hard to follow even if you've watched every episode.

This season is based on the events in roughly the first half of A Storm of Swords, the third (and in the opinion of many, the best) of the thus-far five novels in the Song of Ice and Fire series. The paperback edition of Swords clocks in at just over 1,200 pages.

Ironically, the TV series may be more frustrating for those devotees who have read all of Martin's books because it makes you keenly aware of what the show leaves out and what it adds.

"The first season was really very faithful," says an e-mail from Elio M. Garcia and Linda Antonsson, curators of the exhaustive website devoted to Martin's fiction.

"This past season the writers deviated rather more from the novels and often substituted their own material for what was in the books," the webmasters write. "Some of it was budgetary. But they often seem to become enamored of certain actors or certain actor pairings, and then they end up overusing them."

They cite the prominent story line given Robb Stark (Richard Madden) and his battlefield bride Talisa (Oona Chaplin) in Season 2; in fact, Robb is notably MIA from the second novel, A Clash of Kings.

"Richard Madden's a handsome talented actor," Garcia and Antonsson write, "but they basically kept him around because they liked him personally and wanted to make it a 'season of romance.' "

The 10 episodes about to be telecast may well constitute a season of war. There are two terrible armies, one human and one spectral, mounting imminent invasions from the frozen north.

One last thing: an Easter egg, if you will, that gives you a significant start on Season 3. Think of it as a reward for your continued loyalty to what may be TV's most formidable show.

As the dragons of the luminous Daenerys Targaryen (Emilia Clarke) continue to grow, so do her odds of seizing the coveted Iron Throne. Now here's the secret: The dragons? They don't like sushi.

Keep it under your visor.

Contact David Hiltbrand at 215-854-4552,, or follow on Twitter @daveondemand_tv.