When Mycroft reveals himself to be an asset of MI6, he must explain things to Sherlock and Joan. When neither are as forgiving as he may thought they would be, Joan discovers the reason why he continued to work with the MI6.
After a former MI6 analyst is found armless in the morgue, Holmes and Watson investigate why he was killed and how someone broke in to steal his limbs.
A secret code is discovered in invisible ink that could lead to a huge discovery within the British Intelligence Community, while Joan tries to understand Mycroft's actions.
Just as Sherlock thinks he has solved the case, he finds a fingerprint that changes everything. Be sure to watch Elementary online to see it all unfold.