I went with three of my flatmates and we all decided to dress up a little (although I think I was a little more dressed up than anyone else). This dress has also suffered from my lack of iron, as can very easily be seen.
Pearl-trimmed cardigan: Nordstrom Rack
Gold shoes: Frye via Anthro
The play was fantastic, and it was amazing to see some great British/Irish actors there in real life. Also, Alan Rickman's voice is just beyond amazing in person. Also in the play was Lindsay Duncan, who I love in Rome, Fiona Shaw, who has amazing comedic timing (you've seen her in Harry Potter playing Aunt Petunia), and John Kavanagh, who I didn't recognize at first but upon looking at his IMDB page recognized him from Braveheart.
The Abbey is a lovely and really well-designed theatre. I was literally in the last row, but still could see and hear very well. The set design for this play was amazing, and the seats were even comfortable!