"Always Sunny in Philadelphia" premieres tonight

What to expect: The gang returns tonight for the second part of a crossover with "Abbott Elementary."

• The first part aired in January.

📄 1 fun fact: Rob McElhenney, series creator of "Always Sunny" who plays Mac, legally changed his last name to Mac last month.

What they're saying: "It's such a gift to do something for this long," Charlie Day, who plays Charlie on the show, told The New York Times.

• "And you really have to continue to grow to do it. Even on a show where the characters don't — you have to."