When a cousin is scheduled for major surgery, Richard and Joan Maple volunteer to donate blood. They have been married for nine years. During their drive to the hospital, the Maples argue about Richard's behavior at a party. The intern who performs the phlebotomy is clumsy and rough. He needs three attempts to successfully insert the needle into Richard's vein.

Richard and Joan occupy beds at right angles during the procedure and their blood is taken simultaneously. While watching the blood flow from his wife's arm, Richard experiences deep tenderness for her. An elderly man arrives and chats with the intern. Because Richard has never donated blood before, the three others in the room (Joan, the doctor, and the old man) all expect him to faint, but Richard never does.

The Maples have lunch afterwards. When the check arrives, Richard discovers he has only one dollar in his wallet. He and Joan must both pay. That's how marriage usually works.