In the world of sci-fi geekdom, Joss Whedon​ boasts an immaculate pedigree, having written Toy Story and developed the television series Buffy​ The Vampire Slayer, Angel and Firefly.

With these under his belt, Marvel Studios put their superhero Avengers franchise in his hands a few years ago and like Rumpelstiltskin​, he has spun gold for them.

This latest outing in the franchise sees his characters go up against a villain of their own making.

Thor (Chris Hemsworth), Captain America (Chris Evans), Iron Man (Robert Downey jnr), The Hulk (Mark Ruffalo), Black Widow (Scarlett Johansson) and Hawkeye​ (Jeremy Renner) find themselves squaring off against an artificial intelligence (voiced by James Spader​) that has been created by Tony Stark and Bruce Banner (Iron Man and The Hulk's alter egos).

Whedon​ has had a number of films now (nearly every character has had their own film, sometimes multiple) and his two spin-off television series Marvel's Agents of S.H.I.E.L.D. and Marvel's Agent Carter, to build and evolve complex story arcs and characterisations.

For that reason, if you're already a fan this film pays off throughout and in any number of ways, is resonant and amusing.

For those new to the team, strap in because you're probably not going to understand a third of what's going on but you'll have fun for the most part.

In fact, relentless fun is how I would describe the film, like a rollercoaster ride or an LSD trip that will not end.

There are big dollars up on the screen ($US250 million of them apparently) and frankly in a difficult economy some moments seem casually wasteful, like a battle between Iron Man and Hulk that looks like it might have funded a few medium-sized nations.

Dollars were saved though on co-stars like Gwyneth​ Paltrow​ and Natalie Portman, whose Pepper Potts and Jane Foster characters are mentioned throughout but do not appear.

Technically, the film is excellent, with seamless CGI, and top-notch performances throughout, though moments are dark (literally, squinting-to-see dark).

When my son was younger I used to wave my hand and say "Magic!" as we were approaching the automatically opening door at the Dendy Cinemas, and as the door magically opened he would look at me with such amazement at this miraculous person before him, able to work such feats of wonder.

That look has long gone, unfortunately, but that sense of wonder remains and it is in films like this that you find them – films that feed our fantasies. I've waited 10 years for my boy to be old enough to come to movies like this with me and I look forward to sharing this film with him this weekend.