It all kicked off Wednesday night at the Bell Centre in Montreal, where Perry brought down the house with her new tour. Among the 21,000 fans in attendance was none other than 53-year-old Trudeau, glowing and grooving alongside his 16-year-old daughter, Ella-Grace.

If you were at the Katy Perry concert in Montreal, there's a chance you heard former Prime Minister Justin Trudeau "Roar" among the crowd.

Justin Trudeau attended Katy Perry’s Montreal concert … 2 days after being spotted having dinner and cozy drinks together. The former Canadian Prime Minister was seen in great seats at the singers concert Wednesday night.