->"You know, Ferb. One of the best times we ever had was when we built that rollercoaster. We should do it again, but this time, as a musical!"
-->--'''Phineas Flynn'''
On a day very similar to the very first episode, the not-quite-as-snarky-anymore Phineas remarks that one of the best times they ever had was when they built that rollercoaster, so he decides to do it again, as a musical!