After much anticipation, the unlikely meeting of the two worlds unfolded on Wednesday's installment of "Abbott Elementary." ...

Essentially, "bird law" is a total non-sequitur played off for laughs to show how out-of-depth Charlie is in the real world. It’s a nice wink to "Always Sunny" fans watching the crossover.

The star of the FX series also admits he was initially hesitant about the crossover concept as 'It's Always Sunny in Philadelphia ... with something funny to do. Charlie Kelly fit so naturally ...

The outrageous Abbott Elementary and It’s Always Sunny In Philadelphia crossover proved that the best combinations are sometimes the most unlikely.

When “Abbott Elementary” creator Quinta Brunson mentioned the idea of a crossover episode with “It’s Always Sunny in Philadelphia” — fueled from a conversation with Rob McElhenney ...

"It was a real privilege for me to get to be a part of it, to have them bring us in and make us a part of what they do, which they do so well," says the It's Always Sunny star and executive ...