Betty Cooper's (Lili Reinhart) long-lost brother is making his debut in The CW's "Riverdale" season 2.

The first season of the show wrapped up with a big bombshell that Alice (Madchen Amick) had a son when she was still in high school. As the Cooper matriarch revealed, she and Hal (Lochlyn Munro) fought over it back in the day. However, rather than getting an abortion, she gave the baby up for adoption.

Betty does have a brother in the comics: Chic Cooper, a blond secret agent in his 20s. It has been widely speculated that the character is actually the Black Hood, terrorizing his family for giving him away back in the day. That obviously did not pan out as the mystery killer turned out to be someone else.

Whatever happened to Chic all this time remains unclear, but he is finally reuniting with Alice for the first time in years in the upcoming episode 10, "The Blackboard Jungle." A sneak peek of the episode gives a glimpse at the long-awaited reveal.

"I want to see him, Betty. I want to see my son," Alice tells Betty. It then cuts to a brief scene of the two opening the door to see the blonde Adonis played by relative newcomer Hart Denton waiting. Check out the full trailer below:

Apart from their reunion, other key moments revealed in the promo include the Southside High being closed and all of its students including Jughead (Cole Sprouse) and the Serpents enrolling at Riverdale High. Right off the bat, Jughead is warned to take off his Serpents jacket or face suspension. It also teases a big brawl and Reggie (Charles Menton) calling Veronica (Camila Mendes) a "traitor, and a lot of dramatic stares.

"Riverdale" continues Wednesday, Jan. 17, with "Chapter Twenty-Three: The Blackboard Jungle" on The CW.