The star of the FX series also admits he was initially hesitant about the crossover concept as 'It's Always Sunny in Philadelphia' heads into its 17th season.

Here's a look at our real-time thoughts on tonight's crossover between FXX's It's Always Sunny in Philadelphia and ABC's Abbott Elementary.

After more than two decades of playing Charlie Kelly, Charlie Day‘s beloved It’s Always Sunny in Philadelphia character is finally changing for the better. That’s thanks to the good-hearted Abbott Elementary characters.