"You must be joking, Sherlock! It's in the dairy aisle. Between the yogurt and the cheese."

"Why do I have to do the shopping?"

"Because I'm working late. You don't have a case and you're bored."

"Still tedious. Why can't Mary do it?"

"Mary is doing the baking as a favor for Mrs. Hudson. Helping each other out, Sherlock, is what friends do."

"Mary is your friend, not mine."

"Mary also has to chase after a dozen toddlers all day. Don't know how she manages. I only have to chase after you and I'm knackered."

Sherlock sulks on the couch.

"Just do it, Sherlock."

At noon, John gets a text: I have a case. SH

Congratulations. Don't forget the shopping. JW

Lestrade can't help smiling. Remind Sherlock to do the shopping when he solves the case. JW

On tea break, John's mobile buzzes. Delegated to Donovan. Sherlock went to Bart's. GL

Molly, please remind Sherlock to do the shopping. I owe you. JW

Seriously, John, you've no idea how much! Molly

It's 7:30 p.m. at Baker Street. John is sneaking chocolate chips from the bag and Mary is slapping his hand when the door bursts open.

"You're here!" Sherlock thrusts a small bag into Mary's hands.

"Obviously." She smiles. "Lovely to see you too, Sherlock. Thank you for getting the butter."