My 13-year-old son Rex and I were discussing our next visit to the Odeon multiplex.

“I’d love to see the epic, Dad,” he said without hesitation.

“Which epic?” I asked, my mind reeling with several possible movies.

“There’s only one on right now,” he said. “ Beowulf, of course. You know, the film about that famous Old English epic tale.”

“Sorry, son,” I said, “I misunderstood you. I thought you meant epic movie, not movie about an epic.” “What’s the difference?” he asked.

“Uh, tell you later . . .” I stalled in the middle of a semantic traffic jam. “Sure, let’s go see Beowulf.”

But it started me thinking. What constitutes an epic movie? (And I don’t mean this year’s Epic Movie, a parody of current movies and icons.) Well, for a start I’d say a good reliable director, widescreen, colour and a cast of thousands. And how will those thousands be deployed? Generally, as Roman legions, Napoleon’s army or the children of Israel.

But perhaps that’s about to change now that a couple of talented whiz-kids have become involved with the genre. Early next year Baz Luhrmann is going to wow us with Australia. In this epic, we’ll see the glamorous Nicole Kidman bravely driving thousands of cattle across the wastes of Australia during the Second World War. Truly epic.

But hold on a moment, wasn’t there a film made in 1946 called The Overlanders, in which a glamorous unknown – Daphne Campbell – drives thousands of cattle across the wastes of Australia during the Second World War? Also epic.

The other forthcoming and eagerly anticipated epic is There Will Be Blood, starring Daniel Day-Lewis and directed by Paul Thomas Anderson, best known for Boogie Nights and Magnolia. The script is based on Upton Sinclair’s 1927 novel Oil! Here the plot concerns dealing, double-dealing and family feuding over the ownership of land and oilfields in Texas. Perhaps the epic Giant (1956) springs to mind?

So can we surmise that a so-called epic is simply a tried-and-trusted formula for “epic box office”?

Top of the box-office hitlist comes the religious epic The Ten Commandments, Cecil B. DeMille’s black-and-white silent epic, which first hit the screen in 1923 and made a mint. Hardly surprising that those world-shaking tablets arrived in glorious Technicolor in DeMille’s 1956 version – the fifth-highest grossing film of all time. (In his introductory speech to the movie, he assured us that there would be an intermission. We were in for a long afternoon.)

Also, there were a couple of versions of the box-office hit Ben-Hur, again a silent one in black and white (1925, directed by Fred Niblo) followed by colour (1959, directed by William Wyler and winning 11 Oscars). Before we leave the Bible, let’s not forget The Robe, from 1953, starring Richard Burton and Jean Simmons, which gave birth to a new cinematic process just made for epic movies – CinemaScope.

Way back in 1927 there was another cinematic first in the three-and-a-half hour silent epic movie Napoleon. Directed by the great visionary Frenchman Abel Gance, the film introduced “polyvision” – in which Gance projected three different scenes onto the screen simultaneously. Very effective.

Yes, it seems that Napoleon shares a niche in epic history, along with Jesus Christ, Alexander the Great and Robin Hood. The little French emperor shows up again in Tolstoy’s War and Peace, featuring Audrey Hepburn and her hubby Mel Ferrer, directed by King Vidor in 1956. And there he is again, suffering defeat in Sergei Bondarchuk’s 1968 version. Shot on a new process called Sovscope 70, this eight-hour masterpiece, featuring 120,000 troops, must be the epic to end all epics.

Why is the epic form so engaging to audiences? It’s satisfying to see an easily identified hero participate in mythic-sized conflicts. It’s a relief when complex sociological terrain can be reduced to a good old-fashioned bust-up between right and wrong. Yes, war is prime epic material – just think of Gone with the Wind (1939) and Lawrence of Arabia (1962).

But now a new brand of epic has taken over – the fantasy epic. This includes films such as The Lord of the Rings, the Harry Potter series, Stardust, the Narnia tales, The Golden Compass and yes, Beowulf, in an ever-expanding 3-D world of technical miracles and perfect, beauteous beings who glow in the dark.

Where will it all end? Perhaps Rex will live to take an epic journey himself to the very frontiers of space, in perfect safety. He may even end up storming the gates of Heaven itself – while his dad soldiers on in his humble world of home movies.

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