Can we just take a second to appreciate this comment?
"I did wind him [David Tennant] up though. Because the moment where I do whisper in his ear, I *was* whispering things in his ear. There’s quite a lot of outtakes of him not being able to keep a straight face. But I’m not gonna tell you what I was whispering!"
Alex Kingston - at Hurricane Who Q&A panel, 28.06.2012