Ferenc Krausz was preparing to give lab tours at his Institute when a call from Stockholm reached him at home. “I was not sure whether I was dreaming, or whether it’s reality,” he tells Adam Smith in this call recorded just after the physics prize was announced. “It’s always exciting to see something that no-one could see before,” he says, recalling the thrilling morning in Vienna in 2001 when he first saw that they were able to reveal electron motions with their attosecond pulse technology: “This was just an unbelievable moment which I will never forget!”