But it was all essential to the much-anticipated experience of seeing Harry Potter and the Half-Blood Prince in the IMax, and I for one couldn't wait.

We were like schoolchildren – of which there were surprisingly few – in the queue, and the delay made it all the more thrilling.

The opening sequence – the first 10 minutes only were in 3D - sees the Death Eaters' assault on the Millenium Bridge in London.

Feeling yourself soaring on a cloud of black smoke while wearing comically outsized 3D spectacles is something everyone should experience, and it took my breath away.

This is the film where the dark powers are overtaking the Wizarding and Muggle world alike, so it's a dark instalment in the series.

And as expected, teenage hormones are raging in the castle, with tension between Ron and Hermione finally reaching boiling point, and Harry's fixation with Ginny Weasley.

The Half-Blood Prince has the most heart-wrenching climax of all the instalments so far, as those who have read the book will know.

Although not as poignant as in the novel, the tragedy still comes across, and there is an accentuated sense of unity in Hogwarts throughout the whole film.

A somewhat unwelcome element was the baffling addition of several scenes which were not in the book and had nothing to do with the plot.

These included a long scene where the Weasley family's house is attacked.

Although action-packed, it took up screen time that could have been used to elaborate on other parts of the book which were skimmed over.

This film also has the first appearance of werewolf Fenrir Greyback. Although he looms threateningly, not once it is stated what he is, unless you catch the split-second glimpse of a Wanted poster right at the beginning.

Overall, it was an enjoyable film, and probably my favourite of the six.

Tom Riddle's intriguing history begins to unravel, and there are some real jump-out-of-your-skin moments, not least when Harry dips his hand into the Inferi-inhabited lake.