Pre-heat your oven to 225F.
Place the roast in an oven proof dish (it will need to withstand 500F at one point) and place it in the 225F oven.
If you have a thermometer with a remote probe place it in the centre of the roast. If you don't then start checking internal temp after 2 hours. You are shooting for 125F internal temperature.
When you get to 125F remove the roast from the oven. Let your roast rest for 30-60 minutes while your oven heats to 500F.
While your oven is heating start preparing your gravy.
Add the red wine to a saucepan and simmer briskly until reduced by half. Add your stock and reduce slightly.
After the roast has rested for 30-60 minutes return it to the oven and blast it for 10 minutes to brown and crisp up.
Remove from oven and remove roast from the pan. Spoon off all but 2-4 Tbsp of beef fat.
Place pan on medium low heat. Add half as much flour as you left fat in the pan. If you have 2 Tbsp of fat, add one Tbsp of flour. Make a roux by stirring the flour and fat together. Cook, stirring constantly for about 1 minute. Add the warm stock/red wine mixture slowly, stirring constantly. Bring to a simmer. Adjust seasoning.
Carve the bones out of the prime rib and cut into slices across the grain. Serve with gravy.