Place a large, shallow bowl in a warm oven. Toss the shrimp with the Old Bay; season with salt and pepper.
In a large skillet, heat the EVOO, three turns of the pan, over medium-high. Add the rosemary and garlic; stir until fragrant, about 1 minute. Add the shrimp and cook until pink on the outside, 1 to 2 minutes; transfer to a plate. Add the beer to the skillet and cook until reduced by half, 3 to 4 minutes. Add the stock, Worcestershire and hot sauce and cook until slightly thickened, about 5 minutes. Add the lemon juice and whisk in the butter until melted. Add the shrimp; simmer until just opaque in the center, 3 to 5 minutes. Serve in the warmed bowl topped with celery and scallions. Serve with warm bread for mopping.