Joan wandered into the kitchen and opened the fridge. Sherlock was on the phone again, speaking in Mandarin this time. As she poked around looking for enough food to make a decent sandwich she eavesdropped. It didn't sound like a case. In fact it sounded like—"Are you talking to my Mother?"

"Mary Watson has generously agreed to help me with my Mandarin." Sherlock replied. He paused for a minute. "She says if you hadn't dropped out of Chinese school you could do it yourself."

Joan sighed. "We need to talk about boundaries again. put Mom on speakerphone."