Selena Gomez and hit the red carpet in a stylish black gowns ... while TV legend Jennifer Aniston changed it up with a bright white ensemble. "The Bear" star and Emmy winner Jeremy Allen White looked stylish in a classic black tuxedo.

A couple of Gomez's close friends -- and "Only Murders in the Building" costars -- Martin Short and Steve Martin opted for a pair of stylish black tuxedos.

Their show -- about a trio of amateur podcasters who solve major murders in NYC -- has eight nominations at this year's Emmys ... and, ya gotta think the cast is going to investigate if they don't win at least one or two.

Movie star Saorise Ronan decided to hang with TV folks on Sunday ... arrive in purple top that left her stomach bare and a matching floor-length skirt.

While she's not nominated, her new husband Jack Lowden is up for Outstanding Supporting Actor in a Drama Series for Slow Horses ... and, she's out showing him support.

And, "Baby Reindeer" creator and lead actor Richard Gadd is at the awards too ... where his project is nominated for 11 Emmys -- despite the controversial claims by a woman who is suing Netflix for defamation over the show.

Dan Levy and Eugene Levy -- the father-son duo best known for playing father and son on "Schitt's Creek" -- are hosting Sunday's festivities ... and, they snapped a pic together before heading inside to get ready.

As you know ... this is the second Emmys of the year -- a previous ceremony was held in January after last's year's writer and actor's strikes pushed the ceremony back.