Go tell the Spartans, passerby. That here, by Spartan law, we lie, read the ancient elegy on stone at Thermopylae, the ancient battle site where the Greeks, 300 Spartans and their allies, held off masses of invading Persians in 480 BC. Hollywood, our modern Mount Olympus that churns out fresh myths along with popcorn and soda pop, is taking on this historical battle that defined ancient Greece long ago.

Thermopylae was a narrow mountain pass, wide enough for one chariot, with cliffs on one side and the sea on the other, according to the historian Herodotus. There, a small force led by King Leonidas of Sparta met an invading army of hundreds of thousands of soldiers — perhaps 800,000, according to accounts from the time. After two days of the lightly-armored invaders being slaughtered by the spear-wielding and heavily armored Greeks, treachery enabled the forces of Persia's emperor, Xeres, to outflank the Greeks guarding the pass. Leonidas dismissed the bulk of his army, again according to legend, and his remaining force of 300 Spartans and allies fought a suicidal holding action against the invaders.

The battle ended up a costly victory for the Persians, sort of the Alamo of their invasion, giving the Greeks time, and inspiration, to regroup and defeat them later in the war. The example of the Spartans and their allies has lived on, inspiring military codes still alive today, as well as some of the best quotes in history, such as Leonidas' "Come take them," his reply to a Persian request to lay down his arms.

In 300, which opens Friday and is based on a graphic novel by Frank Miller, filmmakers add fantastical elements to the story of the fight, one whose drama would seem to call for little embellishment. USA TODAY asked Paul Cartledge, author of Thermopylae: The Battle that Changed the World, who has seen a preview of the movie, to give his take on how Hollywood stacks up against Herodotus, whose writings give the best account of the fight:

Q. When the movie Troy came out in 2003, a number of classicists said they were pleased to at least see their field getting some silver-screen time. Others worried they would have to spend class time "deprogramming" students who had seen the movie. How do you view the 300's release?

A: I too am very pleased, if only because it gives us a chance to show why what we classicists/ancient historians do still really matters today (and not only in terms of entertainment). Troy the movie was based on (distantly!) a work of Tfiction — or if you like, a national epic — actually two epics, the Iliad and the Odyssey. But 300 is squarely based on a work of history, the Histories of Herodotus, which was indeed the first work of proper history ever written! So the evidence base of the two movies is quite different (not that we can be sure Herodotus got all his facts right, of course — he was only age 4 or so at the time of the Thermopylae defense, and he had his biases and hobbyhorses like any of us.)

Q. So how does the movie's version of the battle stack up to the historical record, in your view?

A: The historical record is (pretty much) Book 7 of Herodotus' Histories. What the movie leaves out is that Sparta didn't fight the Persians alone but as the head of a Greek alliance that included, most importantly, Athens. Sparta was the greatest Greek military power on land, Athens by sea. The resistance to the massive Persian invasion had to be an amphibious one, both by land and by sea, to counter the Persians' amphibious invasion. So the filmmakers missed out that Leonidas and his Spartans were attempting to hold the Thermopylae pass by land in conjunction with the allied Greek fleet led by Athens just up the coast.

However, there are two points about this Greek alliance: 1. It was tiny — only about 30 Greek cities out of 700 or so who might have joined in the resistance; 2. Far more Greeks fought on the Persian side than on the loyal Greek side!

What the movie adds in is a slew of fantasy fiction, including scary monsters. This is partly to take full advantage of the latest computer techno-wizardry (only one small scene was actually filmed out of doors — the rest in the studio against a blue screen with the background — mountains, sea, etc. — all digitally added on.)

What the movie gets dead right is the Spartans' heroic code (not least the gallows-humor one-liners) and the key role played by women in backing up, indeed reinforcing, the male martial code of heroic honor.

Q. Do you think the Greek world view, and particularly the Spartan ethos, comes across in the movie?

A: There was no single Greek world view, in the sense that there were about 1,000 separate Greek communities, all politically separate — though they had many customs, especially religious, in common, and some common ideological features (e.g., a passion for competition — survival of the fittest in every sense). By general consensus, the Spartans were different — strange, odd — compared to normal Greeks, especially in their single-minded devotion to war (or preparing for it), in the relative freedom and empowerment of their women, and in the men's willingness to die heroically for their country and its ideals.

Q. Can you say anything about your contact with the filmmakers? Can you say how much interest they had in recreating the time period?

A: The filmmakers seem to have read my extensive published work — for example, The Spartans (2004) — and made good use of it. But I was consulted formally only over the question of how to pronounce ancient Greek names — for example, should 'Leonidas' be LeonEYEdas, LeONNidas, or LeonEEdas?

I advised LeonEEdas, but they went for LeonEYEdas, so you can see how influential I was (not).

Q. Are there any other key points about the movie or the battle you think are worth making to our readers?

A: Nothing to add — except a caveat about black and white, 'West' (goodies) vs 'East' (baddies) polarization (taken directly from Miller's original cartoon series — he was the movie's principal consultant). It's never a good thing to do that, I think, and least of all now!

In his 2005 book, A War Like No Other: How the Athenians and Spartans Fought the Peloponnesian War, the classicist Victor Davis Hanson writes about how a civil war in Greece, decades after the repulse of the Persians that started at Thermopylae, upended the Greeks' view of themselves as honorable and brave, a product of that fateful battle. In some ways, the battle set the Spartans up for failure later, setting a bar for fearlessness higher than mere mortals could sustain. But it is remarkable that a relatively small fight about 2,500 years ago could still have renown today.