Now in its fifth season (the first of 10 new episodes premiered on Sunday), HBO’s popular fantasy is as engrossing and entertaining as ever – no small feat for a long-running television series. Creators David Benioff and DB Weiss are on record saying they envision seven seasons for the programme, in line with the George RR Martin's seven novels from which the show is adapted. To date, only five of these hefty tomes have been published (the concluding volumes, The Winds of Winter and A Dream of Spring, are still to come). And though Benioff and Weiss are privy to what Martin has in store, they’ve stated that these later seasons will often diverge drastically from the books.

This is a positive move: the TV series should stand on its own, doing visually what can’t be done in prose – although some of Martin’s more lively descriptions will be lost in the process. Last season’s climactic confrontation between beleaguered dwarf Tyrion Lannister (Peter Dinklage) and his heinous father Tywin (Charles Dance) ended, as in the books, with the Lord of Casterly Rock killed by crossbow while on the toilet - but left out some of the writer's more colourful language. But Benioff, Weiss and their talented creative team do best when they focus less on the microscopic letter of Martin’s tale than on the bigger picture.

For all the show’s narrative complications, the goal each season is invariably the same – the Iron Throne and who gets to sit on it. All the rest is a game of chess, and it’s to the programme-makers’ credit that this particular long-term game invariably feels like it’s hurtling toward the final reckoning.

A large part of this has to do with the series’ ostensible lead. In the first season, Dinklage’s Tyrion provided comic relief, always ready with a pithy, cynical observation about the cut-throat world of the Seven Kingdoms. He quickly became more central to the narrative (to these eyes it was his heroic actions during season 2’s Battle of the Blackwater that made him a superstar), while Dinklage took home Emmys and Golden Globes for his efforts and assumed a more prominent position in the show’s elaborate opening sequence.

So where do we find our protagonist at the start of the fifth series? Probably at his lowest point, emerging dirtied and destitute from a box that’s been shepherded by the eunuch Varys (Conleth Hill) far away from King’s Landing, where Tyrion had been on trial for murder. With Tywin Lannister dead, whatever claim there was to the Iron Throne is now more tenuous than ever. It’s the well-connected Varys’ belief that the best option is to travel to the city of Meereen and pledge loyalty to Daenerys Targaryen (Emilia Clarke) and her army of Unsullied. A lot happens to Tyrion from that point on. (There’s really nowhere for him to go but up.) And by the end of episode four he’s nearer to Daenerys than Martin managed to get him at a comparable point in the books.

The increase in narrative momentum is felt all around: there are bloodily rebellious uprisings, one led by a deceptively soft-spoken character called the High Sparrow (played by the best of the large cast’s new additions, Jonathan Pryce). Over at the 300-mile-long fortification known as The Wall, Jon Snow (Kit Harington) clashes with both his fellow soldiers and the newly installed Stannis Baratheon (Stephen Dillane), who is plotting his next move on the Iron Throne. And there are, of course, the Stark girls, Arya (Maisie Williams) and Sansa (Sophie Turner), both still adrift in body and spirit.

There are plenty more complex machinations where that came from, though trying to summarise it would leave even Game of Thrones fanatics’ heads spinning. But that’s part of the genius of Benioff and Weiss’s approach to this story. They embrace its sprawl, focusing on creating a world rather than on plot detail.

Big picture

It’s hardly important if you can’t tell Ser Jorah Mormont from Tormund Giantsbane, or think the Long Bridge of Volantis is some exclusive nightclub in a metropolitan red-light district. When the scheming Cersei Lannister (Lena Headey) attempts to undermine the newly installed Queen Margaery Tyrell (Natalie Dormer) or the Red Priestess Melisandre (Carice Van Houten) tries to seduce the honourable Jon to join the dark side, the convincing performances overshadow the confusing plot lines.

So much of a good fantasy narrative is dependent on creating a believable world. To this end, it helps that Game of Thrones remains one of the most visually striking shows on television, a mesmerising mix of sumptuously detailed sets and sweeping exteriors (filmed everywhere from Iceland to Morocco to Ireland to Malta) that bring Martin’s world of labyrinthine deceptions and fire-breathing dragons to life. The roster of talented behind-the-scenes collaborators also continues to grow: the first two episodes are directed by former Breaking Bad cinematographer Michael Slovis, whose keen eye results in a number of memorable images like the desperate Tyrion’s point-of-view from inside his claustrophobic crate or Daenerys watching, wide-eyed, as one of her beloved dragons soars over the nighttime sky.

These scenes encapsulate the overall experience of Game of Thrones – simultaneously intimate and expansive. It’s a show as capable of portraying one character’s specific longings as it is widening its gaze to take in a soul-stirring view. And it always leaves the viewer wondering what other lands and adventures might lie over the horizon.

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