The 'Arrow' universe has been especially abuzz with the imminent arrival of Grant Gustin's Barry Allen in tomorrow's "The Scientist," making The CW extra generous with its promotional goodies. Yet another clip of Barry Allen's flashy 'Arrow' integration has arrived, along with a few new updates on future DC characters to come!

The latest look at tomorrow's super-powered 'Arrow' installment (via THR) features Barry Allen working with Felicity, coming a bit uncomfortably close to deducing the Arrow vigilante's methodology in the process. Barry clearly has his own infatuation with the hooded hero, but what about his past gives him a special insight into costumed crimefighters, we wonder? The mystery deepens...

Elsewhere, it seems the earlier leaked teaser hints of future 'Arrow' appearances from the likes of The Question and Red Hood, among others, may have been a bit speculative, as Warner Bros. representation confirmed no official plans to feature the masked characters in future 'Arrow' installments, at least for now. On the plus side, it looks as if Oliver will at least tend with the Clock King this season, said by TVLine to possess “the mind of a chess grandmaster, and can envision all the interlocking pieces of Starling City and adjust them in favor of his crimes.”

While we wait for Barry Allen's speedy approach, check out the latest clip from "The Scientist" above, and tell us what DC characters you'd like to see enter the fray in the comments!

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