For the turkey: The day before cooking, pat the turkey dry and sprinkle outside and inside with 1 1/2 tablespoons salt and 1 teaspoon pepper. Refrigerate, uncovered, overnight. The next day, remove the turkey from the refrigerator and let it come to room temperature.
Set a rack into a large roasting pan and place the turkey on the rack. Stir the butter and paprika together in a small bowl. Carefully separate the skin from the breasts and rub some of the butter between the skin and flesh. Rub the remaining butter all over the surface of the turkey.
Preheat the oven to 450 degrees F.
Pour 1 cup water into the roasting pan. Transfer to the oven and bake for 30 minutes. Adjust the oven to 350 degrees and continue roasting, rotating the pan halfway through, until an instant-read thermometer inserted into the thigh (though not touching the bone) registers 160 degrees, about another 1 1/2 hours.
Transfer the turkey to a large cutting board and let rest for 20 to 30 minutes while you make the gravy. Reserve the juices from the roasting pan.
For the gravy: Heat the oil in a large saucepan over medium-high heat. Add the reserved turkey neck and giblets and cook, turning occasionally, until deep golden brown, about 8 minutes. Add the butter and onion; cook, stirring, until the onion has softened, about 4 minutes. Sprinkle in the flour; cook, stir and scraping the bottom, until golden brown, 4 minutes. Stirring constantly, gradually add the chicken broth and the reserved pan juices. Bring the liquid to a boil, then stir in the cream. Cook at a brisk simmer until slightly thickened, about 10 minutes. Season with salt and pepper. Strain through a fine-meshed sieve into a large gravy boat.
Carve the turkey and serve with the warm gravy.