Yes, about 2 and a half hours.
I took my son to see one and we loved it; my only complaint would be the cost of the programs when you've already forked out loads for tickets - they were an additional £10. Also, because there's an interval, take some food/snacks and don't buy the extortionate ice-creams.
As a result, we've not been again as I cannot afford that sort of money....worked out a lot dearer than a top class panto - over £100 for 2 of us *groan*.
Perhaps the tickets aren't as expensive now, but I doubt it!