I am having trouble understading the following sentence, which is extracted from the NYT:
Even those who have spent the last 14 years pining for a sequel to “My Big Fat Greek Wedding” — by most accounts, the highest-grossing American romantic comedy — will rue that longing when they experience “My Big Fat Greek Wedding 2.” The imagination expended on the title being a fair indicator of how much was lavished on the rest of this embarrassingly awful retread.
I cannot find a principal verb in this sentence, confused by the structure. Can anyone please explain?
Thank you in advance!