The cast of Riverdale Season 3 continues to grow with the additions of Gina Gershon (Bound) and Trinity Likins (Christmas in the Air, Unspeakable) as Jughead's mother and sister, respectively.

The announcement was made during the Riverdale Panel Sunday at New York Comic Con. Gershon will play Jughead's mother, Gladys Jones, with Likins taking up the role of Jughead's sister, Jellybean "JB" Jones. Both actors will debut on the Dec. 12 episode of The CW drama.

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Gladys is described as a businesswoman and former Serpent with a GED "who runs the salvage yard (chop shop) that doubles as a Serpent compound." When Gladys gives an order, the Serpents jump to attention. Likins' Jellybean "JB" Jones lives with her mom in Toledo, is wise beyond her years and is a con artist, just like Gladys.

Gershon's television credits include FX’s Rescue Me, HBO’s Curb Your Enthusiasm, Amazon’s Red Oaks and Lifetime’s House of Versace. She also won Best Supporting Actress at the Toronto Film Festival for Killer Joe, and appeared in Face/Off, Bound, and The Player. Likins landed the lead role of Amelia in the Hallmark holiday movie Christmas in the Air in just her third professional audition, and had a recurring role as Emma in the CBC miniseries Unspeakable.

Returning for its third season on Wednesday, October 10, at 8 pm ET/PT on The CW, Riverdale stars KJ Apa, Lili Reinhart, Camila Mendes, Cole Sprouse, Madeleine Petsch, Ashleigh Miller, Casey Cott, Mark Consuelos, Skeet Ulrich, Marisol Nichols, Madchen Amick, and Luke Perry.

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