Bruce was working pretty hard, having another angle on trying to cure the Hulk. He'd been going at it for awhile, his uneaten lunch was over to the side along with a cold mug of coffee on the table next to him. He had his eyes in a microscope with an eyedropper poised over the slide.
He didn't move for a second as Tony came in, not wanting to mess up the experiment. "Put that down," he said as if he had eyes in the back of his head and saw that test tube he picked up. Only then did he let two drops of solution hit the slide and focused the lens. "Did you need something?"