In the end credits of every episode of It's Always Sunny in Philadelphia the credits for the production company RCG (formerly RCH) include a hidden audio message. The messages are recorded by the executive producers (Rob McElhenney, Charlie Day, and Glenn Howerton) and are played backwards.
Season 1 ---
Season 2 ---
Rob and Glenn: - "Is a brown, is a brown, is a brown". - "Good work". (2 times)
All three (singing): "Clown baby, brown clown clown baby, brown clown". "02x05" Only
Season 3 ---
All three (singing): "Make it brown". (4 times)
Season 4 ---
All three (singing): "Clown baby, brown clown clown baby, brown clown".
Season 5 ---
Rob: "Next stop - brown town".
Charlie (singing): "The eagle's born out of thunder". "05x07" Only
Rob: "Sorry for wasting your time and money, but thanks for your money".
Season 6 ---
Glenn: "BROWN - now in HD".
Season 7 ---
Charlie: "Seven seasons of brown".
Season 8 ---
Rob: "The browning's will continue". [PROOF]
Season 9 ---
Charlie (singing): "The eagle's born out of thunder".
Season 10 (as of episode 1) ---
Charlie (repeated 3 times): "I got chicken in Philly"
Season 11 ---
Glenn: "Brown is awesome" (3 times).
Season 12 ---
Rob: "I'm on the brown train". Glenn: "Thanks for watching, it's been brown". Glenn: "Goodbye everyone, it's been brown".
- On a white background, we see three men (Rob McElhenney, Charlie Day and Glenn Howerton) wearing hoods, jackets and sunglasses. According to Glenn, "RCH never stood for Rob Charlie Howerton". Here is his Tweet from August 13, 2011: "I'll give you guys a hint: RCH is an acronym for a very small unit of measurement. Most carpenters will know the answer". This article says that "a red cunt hair (also RCH, red pussy hair, and red one) is a figure of speech used to represent infinitesimal length".
- The abbreviation RCG probably stands for "Rob, Charlie, Glenn".
- At the end of the 1st Season finale, the message had an echo.
- The use of the word "brown" in most of the messages is possibly a reference to Philly band Ween who have made the word their own, meaning bodacious. And this show is definitely really, really brown.
- "Clown baby" - it's a nickname, which is was made up by Dennis for Charlie (as the Paddy's underground street fighter). ("Hundred Dollar Baby")
- "The Eagle's born out of thunder" is a line from the "Birds of War" song in Season 5's The Gang Wrestles for the Troops.
- "They got chicken in Philly" is a quote from the first episode of season 10; The Gang Beats Boggs.