To put it mildly, John Sheppard was confused. When the alarm had gone up that the Wraith had shown up, he ordered a retreat to the stargate and headed in the direction that he had last seen McKay. Rodney had an uncanny ability to end up in the worst possible spot and he had been horrified to see McKay in the grip of one of the Wraith. He knew that he was going to be too late to stop it from feeding and despair briefly took hold before being replaced by sheer and unadulterated fury when one of the new science team took aim and shot McKay straight through the heart. The S.O.B. didn't even hesitate and hadn't even bothered aiming at the Wraith until it dropped McKay and started in their direction.
He briefly considered letting the thing have the man who had just killed his best friend when he decided he'd rather be the one to kill the bastard. Once the wraith fell, he ran toward the body of his friend and grabbed the man kneeling beside Rodney pulling him to his feet and aiming a fist at the startled face. John was even more surprised when his prey ducked the fist, caught his arm and had him in an inescapable headlock before he had a chance to react to missing his target. The words the man was shouting slowly registered and he stopped fighting only to be released immediately when the man realized John had regained some degree of control.
Looking at Rodney's body, he turned incredulously to the man he had been fighting with,
"What do you mean he's not dead? Look at him, he's not talking; he's not even breathing. You shot him in the heart and you say he's not dead."
He dropped to his knees as grief took hold and reached toward Rodney's body only to have a strange mix of terror and relief take hold as the formerly deceased took a deep breath followed by a choking gasp and tried to sit up. John tumbled backwards as Rodney was helped to his feet by the stranger who kept smiling that damn irritating mysterious I know something you don't know smile. Scrambling to his feet, he ignored the bloodstains on Rodney's chest and gave the bewildered Physicist a brief hug before turning to the stranger.
"I think you have some explaining to do."