The next “Previously on Arrow…” clip might take a while. It's nerd vs. nerd as Felicity takes on the Calculator in Arrow's 'Unchained' - Los Angeles Times News ...

Season 4 Episode 12 of Arrow, “Unchained”, was a parade of old faces but in the end, they were all eclipsed by a single brand new one: the Calculator’s. Introduced in an unassuming fashion ...

Team Arrow's battle against Damien Dark grows desperate this week as new episode images show a team up with Felicity's dad, The Calculator.