It's not often I arrive at the theatre in a grump, but a long and unexplained bus diversion in London's Whitehall – G20 was last week, guys – threatened to make me late for the 10th anniversary performance of Mamma Mia! But I got there in time and, just as I was on 6 April 1999, was immediately transported to a mythical Greek island where a wedding is about to take place.
Ten years on, Mamma Mia! – a love story set to Abba songs – still doesn't rival Sophocles, but it remains as stonkingly, wonderfully, unbelievably good as the first time I saw it. The presence of Abba's Björn Ulvaeus and Benny Andersson at the Prince of Wales theatre merely added to the occasion but, in keeping with their resolute unstarriness, big-name celebs were few and far between in the audience.
I noticed some differences post last year's Meryl Streep film version; the audience was quicker to pick up on the show's several layers of irony and the occasional smutty line. Writer Catherine Johnson's inspired segues into the opening lines of songs were more noisily appreciated than I remember. I had to stop myself singing along to every song and saved myself for the audience singalong at the curtain, when Benny and Björn made sweet speeches of thanks to casts present and previous.
But what is it that makes the show so appealing? Well, quite apart from having some of the finest pop songs ever written, Mamma Mia! is the ultimate feel-good tale of love conquering all. It is completely uncynical and consistently compelling – it's the perfect show for someone who says they don't like theatre, or who "doesn't do musicals". I've seen the show a few times in various locations and, with the exception of last night and the first night in 1999, have paid top dollar for the privilege – a real testimony to its attractions for someone used to seeing shows for free.
I'm not alone: Mamma Mia! has a high percentage of repeat audience members among the 32 million people who have seen it in the 190 cities where it has played, and at any given time it is being performed on at least three continents. Not bad for a show that even Johnson thought might appeal only to Abba fans. How wrong she was, but then again, so was I; when I interviewed her in 1999, keen Abba fan that I was, I had no idea it would be a global hit.