This is actually a pretty good video...
Click to view
In another life, I would be your girl
We'd keep all our promises, be us against the world...
♥
In another life, I would make you stay
so I don't have to say you were the one that got away...
...and now, for the music nerd in me...
[From Wikipedia] "The One That Got Away" was written by Katy Perry, Lukasz Gottwald and Max Martin and produced by Dr. Luke and Max Martin. It is a midtempo dance-pop song positioned on the piece of E major and has a rhythm of 138 beats per minute. (138 bpm, what a random factoid.)
The song follows the chord progression of E-G#m-C#m-A and Perry's vocal range and spans two octaves from B3 to E5. (Cool, now I know the chords. Thanks Wikipedia!)