The audience clapped and whooped after every single song, like it was the finale.
I was going to be annoyed.
But resistance is futile when it comes to Hamilton.
Every song deserved the screams of approval.
The story of one of America's founding fathers, the first Secretary to the Treasury, the man who helped draft the US Constitution after American Independence, is on paper a potential hard sell to British theatre audiences.
After all even many Americans know little about the man who graces their ten dollar bills.
But that it works so extraordinarily well on stage is down to the brilliance of the songs, lyrically intricate, historically authentic, foot tappingly addictive, I found myself unavoidably nodding my head along to the hip hop beats, the rapping and the RnB rhythms.
The fact that the soundtrack to Hamilton was already a massive success before Lin Manuel Miranda's musical made this much hyped trip across the pond, having conquered at the Tony's and the Grammys, and even with a Pulitzer prize, has helped ensure Hamilton plays to the converted.
But the music works superbly even if you're not one of the record breaking number who've already bought the CD.
The mainly non-white cast of largely unknown performers is without exception astonishingly good.
Jamael Westman as Alexander Hamilton is excellent - but in truth that applies to so many of his co-stars in this fascinating story.
When Hamilton first arrived on a Broadway stage, endorsed by the likes of the Obamas no less, it was the perfect production for the times.
The immigrant story of America told pointedly by a black, Asian mixed-race cast, at a time when America had a black president.
When President Trump arrived, it's significance only grew.
His Vice-President Mike Pence was memorably addressed from the stage when he went to see the show, with the actor playing Aaron Burr, Hamilton's nemesis, speaking in defence of diversity.
To sit in the West End, watching a diverse cast perform diverse musical styles, felt fresh and important at a time when many are calling for better diversity in British theatre after years when the issue has seemingly been ignored.
Critics in the US and here have suggested remortgaging your house to ensure you get a ticket to see it!
Far better, if you're loathe to spend an eye watering £200 on a ticket, to apply to the lottery scheme for £10 tickets.
President Trump called Hamilton overrated (without seeing it).
It is not overrated.
It is about as exhilarating a theatrical experience as you'll ever have. Worth every standing ovation. And all the Olivier awards that will surely come its way.