This summer, however, the thrills and jolts of the blockbuster season have highlighted the more elusive and subtle element in Spielberg’s summer formula — moral inquiry.

The Dark Knight, the latest instalment in the Batman series, pulls off the most marvellous trick courtesy of Heath Ledger’s performance as The Joker. Not only does it have actors looking directly out of the screen at popcorn munchers delivering lectures on the nature of a moral society — and the moral nature of our society — it manages to seem quite serious and important. Audiences must constantly remind themselves this is a summer movie about a mask-wearing man in tights trying to catch a giggling man wearing too much lipstick.

The man in the lipstick, The Joker, proposes a compelling analysis of our society. “Most people are only as moral as the world allows,” he tells us. In other words, we’re all moral cowards, happy to be good, or appear good, at our convenience and someone else’s expense. Who has not been tempted to such cynicism?

Later The Joker sets up a social experiment to test his theory: will good citizens murder a boatload of helpless prisoners (hardened, evil-looking criminals all) to save their own skins? It isn’t until the citizens rise above self-interest, risk their lives and trust the criminals that Batman seems to gain a sort of upper hand over the unfunny clown.

Just defeating the bad guy isn’t enough to provide resolution and let the credits role on The Dark Knight. In this case, Bruce Wayne in cape, rubber ears and tights has to ride off into the gloom of Gotham’s night like Shane on the crest of a hill with the sun setting behind him. Batman must sacrifice himself — his happiness and the approval of his peers — for the good of a better society. He chooses to become an outcast, to take on scapegoat status.

In The Dark Knight morality does not come cheap. Not only is it hard to tell right from wrong, good guys from bad guys, but moral decisions require sacrifice. The audience can never be quite sure when it’s time to cheer.

The tone and cinematography in Hancock is much brighter than in the brooding Batman flick. Hancock is an unshaven, alcoholic, misanthropic, lonely super-hero who plies his trade sans cape and tights in sunny southern California. Though Hancock saves lives, defeats criminals and consistently chooses to use his power for good, people don’t like him or the mess he leaves behind.

With great power comes great responsibility? Will Smith’s Hancock would treat Spiderman’s adolescent moral theory with contempt.

Hancock’s big struggle is not with a criminal genius threatening to destroy the city; that’s the easy part. He has to deal with a public relations agent trying to remake his image. It is a struggle because Hancock has yet to discover who he really is.

It turns out Hancock is a Greek god suffering amnesia. He has forgotten his divinity and the silly, venal human race has gone from indifference to despising the god who metes out justice and saves Los Angeles from Los Angelinos.

It is quite a daring and serious proposal from such a light, funny and oddly warm-hearted movie. Here we have the citizens of Los Angeles with a god living amongst them, but they actively hate their god because he refuses to present his program of justice through good, professional PR.

Of course, lots of stuff blows up real good too.

The Incredible Hulk has always had the moral plot dynamics of Spielberg’s Jaws to work with. Like the big rubber shark, The Hulk is morally neutral. As the big green man says himself, “Hulk smash!” The moral tale is in how the puny humans react to The Hulk.

The military-industrial complex, seen through William Hurt as Gen. Thaddeus “Thunderbolt” Ross, wants to harness The Hulk for war. His daughter, Liv Tyler’s Betty Ross, wants to pave the way to a more human Hulk with human love. Between these opposite polls there remains the rest of us trembling and paralysed by fear.

The Marvel comic of many years past was a Cold War tale. It is telling that with the easy substitution of terrorists for communists it still works. The Hulk still shows an American empire manipulated by fear and tricked into blind rage.

Wanted is as wild a ride in the cinematic dark as any of these. It’s a film full of superpowers but no super-heroes.

Russian director Timur Bekmambetov gives us a cinematic comic book far less Manichean. There’s good and evil, light and dark, right and wrong, but it’s very hard to tell the difference. James McAvoy as office drone-turned-finger-of-fate Wesley Gibson has the confusing job of discovering both who he really is and who is on the side of the good. He can’t know one without the other.

Of course moral ambiguity is not the same thing as moral complexity. The tangle of moral truth and history is presented to us in a striking image of a ruined loom in a textile factory where all the strands of history are woven together into a code to be read by a team of incredibly talented assassins.

So what do we do when we discover we are no longer on the side of the good? What do we do when we parse out a moral code according to some mechanical formula? How do we advance from our comic-book years of moral adolescence into moral maturity?

“Who am I now?” asks Gibson. “This is not me fulfilling my destiny. This is not me following in my father’s footsteps. This is definitely not me saving the world.”

Most of the audience can say the same. But Wanted won’t answer the question for us. Strangely for a summer blockbuster, this movie won’t let us off the moral hook by blowing up the bad guy. “Grow up. Face your complicity in the immoral world,” urges the movie as bullets fly zig-zag patterns around us.

Oh, what a tangled web we weave in the dark of this summer’s cinema.