With the second episode of season 3, I'm giving Arrow its first official Strike.
You can read about my early relationship with Arrow here. Season 2 continued to be excellent and finished very strong, but it also started to make its main weakness very clear. Laurel (played by actress, Katie Cassidy).
I've heard some explanations of why Cassidy seemed to lose the acting skills she had in season 1, the most common being that she got skinner and, honestly, odder related to the addiction Laurel was dealing with. Not really a great excuse for her heavy-handed acting.
Once Laurel's sister Sara was introduced as Black Canary I've been worried that, like in the comics, Laurel would become the second Black Canary (the first comics' Black Canary being her mother, who worked with the Justice Society). We did see Laurel fight in the first season, and even once or twice in the second, but her scrawny, Hollywood build would be hard enough to sell as the combat-heavy, street-savvy Canary even if her acting was stronger. It's not and it's been confirmed that Laurel will eventually take on the mantel of Canary.
I could have given this first Strike during any number of episodes of Season 2 related to Laurel, but the rest of the story was intriguing enough that I could ignore any scenes she was in. With Sara's death at the end of the first episode and it becoming clear that Laurel will be taking on a stronger role, her weak acting in episode 2 has made this Strike a necessity.
So far, the third season is paying off well and I'll continue watching it, though if Cassidy's acting skills don't improve, and they don't spend a significant amount of time training her (the Sara Black Canary trained with the League of Assassins for 5 years and had years of field experience on top of that), this could be the worst interpretations of one of my favorite DC heroes; since Huntress is regularly handled terribly in live-action (both Arrow and the short-lived, Birds of Prey), I'm not sure I can take watching a terrible Canary as well.
If you want to see excellent versions of Canary (and Huntress, Batgirl, Zatanna and more for that matter), check out Justice League Unlimited Seasons 1 & 2 and Young Justice Season 1 & 2.