Selena Gomez led the 'SNL' studio audience in a wholesome 'Barney' singalong

If you watched Only Murders in the Building then you knew going in to expect a good time from Saturday Night Live with Selena Gomez hosting. And if you didn't watch the hilarious Hulu whodunit, first, find a way to correct that, and second, this opening monologue gets things off to a great start.

Gomez comes out swinging with...