The Beatles' "Can't Buy Me Love" lasts 2 min 11 seconds.

Wagner's "Rhinegold" takes 2 hours and 35 minutes to make the same point.

Still worth seeing though, particularly at ENO. I saw their concert version (= singers on a bare stage, sometimes moving about a bit) a couple of years ago, and this year they're staging them all (= sets and acting too) with (I think, but haven't checked) the same cast. It does make a difference.