The first footage from Rick and Morty season 4 was revealed in a tweet from the official Rick and Morty Account. You can watch it below:
*Ominous beeping noise* FIRST LOOK AT RICK AND MORTY SEASON 4 *Ominous beeping noise* @adultswim pic.twitter.com/FtduZbdHHa
— Rick and Morty (@RickandMorty) July 19, 2019
Source: IGN.com First Rick and Morty Season 4 Footage Revealed