Season the blackfish with salt and pepper. In a large skillet, with a lid, over medium heat, heat the olive oil and butter. Add the fish and saute on each side for 3 minutes. Remove the fish and keep warm.
To the pan, add the garlic and cook 1 minute. Add the tomatoes and cook 2 minutes. Add the basil and wine and bring to the boil. Reduce heat and simmer. Place the fish back in the pan over the tomatoes.
Place clams around sides of saute pan. Return to simmer and cover with the lid. Cook until clams open, about 3 minutes.