The Knave of Hearts was played by Paul McGillion on Once Upon a Time. Here he's played by Michael Socha.
Screwed by the Network: ThelatestshowtomarchbravelyintoABC's long-cursednote the shows listed here only comprise the post-Ugly Betty era; nothing scripted between 1982 and 2006 was able to survive more than a season Thursday 8pm timeslot, one where it has to deal with The Big Bang Theory and The X Factor. Also the latest that won't be marching out - it debuted to a mediocre 1.7 Adults 18-49 rating, and cratered to a 1.2 in week two. ABC has admitted that they screwed up with the scheduling (it was, at one point, intended to fill Once Upon a Time's slot during its midseason hiatus, where it would have had a built-in audience). However it was always intended to be a one season show from the start, with additonal seasons being possible if the show was a success.
Episode 13's promos officially refer to it as the series finale.