After weeks of speculation, last night's 'Arrow' season 2 installment "Suicide Squad" gave fans an unexpected treat in featuring a sly cameo from fan-favorite Batman villain Harley Quinn. The character went unnamed (save for one very recognizable voice!), but see for yourself with Harley Quinn's cameo among the "Suicide Squad' of the 'Arrow'-verse!

Just as we first predicted when promos highlighted a mysterious pigtailed blonde among those in the A.R.G.U.S. cell, 'Arrow' producers included a brief treat for fans during last night's "Suicide Squad," wherein a shadowy "Deranged Squad Female" in custody offered counseling to "cuties" Diggle and Lyla, noting her background as a trained therapist. We never saw the character's face, nor heard her name, though the voice unmistakably belonged to actress Tara Strong, the current voice of Harley Quinn in the 'Arkham Asylum' games, among others.

Harley Quinn has since become and integral member of the "Suicide Squad" in current DC comics, though the brief appearance also ostensibly confirms the existence of Batman somewhere in the 'Arrow'-verse, at least theoretically, following the origin chain from Joker to the Dark Knight himself. Given the loosely-credited nature of the appearance however, as well as FOX's upcoming 'Gotham' and Warner Bros' 'Batman vs. Superman,' we wouldn't hold our breath for any major Bat-crossovers in the 'Arrow' universe just yet.

Well, what do we think? Is Harley Quinn's brief 'Arrow' crossover a Bat-signal to the CW drama's DC future? Watch the "Suicide Squad" cameo above, and give us your thoughts on future Bat-characters in the comments!

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