Peel the shrimp and butterfly them by cutting three-fourths of the way through along the back. Remove the vein while you're at it. Leave the tail on or not, as you prefer.
Arrange the shrimp, split side up, on a baking pan or pizza pan covered with a sheet of aluminum foil. Season with salt and more pepper than you might ordinarily use.
Heat the olive oil in a small saucepan over medium heat until it's fragrant, then add the garlic. Cook for just one minute, then remove from the heat. Stir in the lemon juice.
Drizzle the olive oil and garlic over the shrimp. Put the shrimp under the broiler and broil for three to five minutes, depending on the size of the shrimp. The shrimp should be firm. Serve immediately.