He had a brief but somewhat memorable role in the Zelena arc of Once Upon a Time. At first we think he is Emma Swan’s real boyfriend when she got made-up memories of a “normal life” in Boston.
But turns out he knew all along that Emma Swan was who she really was.
And he turns into a killer flying monkey when she breaks free of her curse.
Turns out Walsh was really the Wizard of Oz.
And he was a magical-less man just like the real Oz stories. But Zelena turns him into her own pawn.