Season one, episode two
This is a small scene, but it has personal significance for us. You see, as book readers, when Balfe was announced as the actress playing Claire, we weren't sure about her — which we were obviously very, very wrong about. But anyway, the series premiere helped tremendously in us seeing Balfe as Claire, but it was this confrontation with Dougal Mackenzie (Graham McTavish) when Balfe truly becomes Claire for us.