No, but seriously there’s this fic in my head where Oliver has a mental break because of everything he’s been through. He starts seeing ghosts turn into monsters in his head. Felicity and Diggle need to restrain him, hide him away because there’s no way they can let him loose in the city when he thinks he’s in hell’s version of Lian Yu or with the Bratva or Hong Kong. He needs help they can’t give. Oliver needs someone who’ll help him make peace with his past, someone familiar with the ins and outs of a mind so riddled with scars.
Of course they can’t get just any city psychiatrist, they couldn’t risk them knowing Oliver’s identity. They definitely can’t trust Waller and ARGUS, Oliver was too vulnerable, too susceptible to whatever manipulation they might inflict. It’s Lyla who leads them to an unlikely ally, someone Deathshot would have warned them against if he had lived, someone who had intimate knowledge of minds mangled beyond belief.
The person formely known as Dr. Harlene Quinzel, Harley Quinn.