Rex at the Royal hosts a Lowcountry pop-up before its opening on South Street

Rex 1516′s move into the Royal Theater building next door should be completed in October, but first, owners Jill Weber and Evan Malone of Sojourn Philly are hosting a one-day pop-up on Friday, Oct. 1 in the outdoor garden at their Jet Wine Bar across the street, 1525 South St.

The idea is to show off a few forthcoming dishes from the newly renamed Rex at the Royal, whose menu pays tribute to the early 20th-century Black chefs who adapted traditional Southern fare — notably the Lowcountry cuisine of the Southeast Atlantic Coast — to Philadelphia.

Weber, an archaeologist, and Malone, an entrepreneur, say they want to tell the story of the neighborhood a century ago, when the Royal was a movie house and cultural center of Black American life in what is now Graduate Hospital or Southwest Center City. The Royal’s brick facade remains; the rest of the building has been rebuilt into apartments and houses.

Brooklyn-born chef Aaron Paik, of Dominican and Sicilian heritage, counts Miami’s Scarpetta and the Sanctuary Hotel of Kiawah Island, S.C., on his resume. Paik developed Rex at the Royal’s menu with chef Valerie Erwin of the late Geechee Girl Rice Cafe. They’ll focus on Atlantic seafood, grains from Marsh Hen Mills, local produce, and sustainable meats.

On Friday’s a la carte menu will be a burger with bacon, spicy pimento cheese, crispy red onions, and butter lettuce, as well as a “burger” made of West African black-eyed pea fritters with samba sauce, tomato, crispy red onions, and shredded Romaine; shrimp and grits; beef and beans; mussel salad; banana pudding cheesecake for dessert; plus four wines and two cocktails.

It’s walk-in only, from 5 to 9 p.m.