"Sunny's" two-part season finale kicks off with the Gang returning to their high school for a reunion and the momentous reveal of Mac's full name. I won't spoil it, but I couldn't have been more satisfied with the execution.
The episode basically consists of the Gang reconciling their bombastic egos with the reality that all of them (including Dennis) were losers in high school. Dennis, the most delusional of the bunch, lords himself over his former classmates and is honestly miffed by their indifference to him. (This builds up to somewhat of a nervous breakdown in part 2). Dee cozies up to the "cool kids" who bullied her during her "Aluminum Monster" years in a callback to her Stockholm Syndrome from "The Gang Gets Held Hostage," until Cricket blows up her spot. Charlie, the saddest and most realistic one, reverts back to being the scrub who humiliated himself for others' amusement. Mac, who was a narc-turned-dealer in high school, reverts to his old high school persona (the narc/rat) as well and is punished with an atomic wedgie. By the end of the episode, everyone from The Gang is humbled, disgraced, and ready for revenge.
"The High School Reunion, Part 1" provides an unusual amount of insight into the characters and how they became such wretched adults. This makes the episode exceptional, especially when you consider that the show is in its seventh season and that "Sunny" doesn't exactly tout character development as a major focus. The point was largely to build up to Part 2, the finale of the finale, but there were lots of laughs on the way. There were plenty of callbacks to earlier episodes, including appearances from the Waitress, Maureen Ponderosa, Brad (the waitress' ex-fiance), and Cricket. The highlights of part 1 for me were Dennis' self-delusion and how pitiful Charlie was. Beneath the humor, there's some dark, dark stuff going on, and the original writing dream team of Rob McElhenny and Glenn Howerton predictably struck the right balance. While it wasn't as riotous as "Frank Reynolds' Little Beauties" or "Thundergun Express," it was a strong episode on the whole and a good way to begin ending the season.