The 'Abbott Elementary' EPs talk jokes cut from 'Always Sunny' crossover, including backstories for Frank and Mr. Johnson.

It’s always busy for the It’s Always Sunny in Philadelphia cast.

Rob McElhenney teased that the Abbott Elementary/It's Always Sunny in Philadelphia Season 17 crossover may "surprise quite a few people." ...

Compendio: Frank is established as Dennis and Dee’s father when he first appears in Season 2 of "Always Sunny" — though the audience later finds out that he is not their biological father.

It's Always Sunny in Philadelphia is about to release ... However, the best character pairing was Frank (Danny DeVito) and Mr. Johnson (William Stanford Davis). These two are a natural fit because ...

Once again, it all comes down to Frank’s love for Shadynasty. While it might not make most fan’s lists of best It’s Always Sunny in Philadelphia episodes, Season 7’s fifth episode “Frank ...

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

The Gang' cleaned up its act when it appeared on the ABC sitcom. But Rob McElhenney says the 'Abbott' teachers will curse and ...

We're closer than ever to knowing a premiere date for "It's Always Sunny in Philadelphia" Season 17. Series co-creator and ...

We always knew that It's Always Sunny in Philadelphia's Frank (Danny DeVito) would easily match Abbott Elementary's Mr. Johnson's (William Stanford Davis) weird. But we just didn't know how much.

The "It's Always Sunny in Philadelphia" crew is headed to "Abbott Elementary" in the first of two crossover episodes.

Charlie learns to read, Dee impersonates Ben Franklin, and Frank fights raccoons. We don't quite know what's up with Dennis though.