Suddenly a gun materialised in John's hand, and Sherlock blinked in amazement.

Pressing a finger against his lips John gestured for silence as he stepped through the door.

Swallowing back questions along with his shock Sherlock followed, keeping close behind the blond doctor.

Off to their left was a closed door and from inside came the sound of raised voices. Sliding closer they both listened.

It sounded as if Dimmock was threatening the homeless kids with violence if they didn't give up the whereabouts of the scientist Sherlock Holmes and his blind friend.

Greg snarled, saying something about how only a useless coward threatened the weak and helpless, earning himself a crack across the temple from the butt of a handgun which made both listeners wince.

That was all it took to trigger a stream of vitriolic defamation of Dimmock's character and professional abilities from the Detective Sergeant, and John stifled a grin. God bless Sally Donovan's belligerence.

John and Sherlock used the cover of her diatribe to slip unnoticed into the room, taking the brief moment before discovery to note the positions of every weapon and potential threat.

John cleared his throat.

"Put the gun down carefully Dimmock, and step away from it." He said, and the officer turned to see Moriarty captive at the business end of John's Browning.