Not a great story arc, and many of the jokes are the same. Harry does the same speaking in my language gag we've seen in many episodes, the same jokes in how he mangles his delivery of English in exactly the same ways.
The only interesting edge and one that was interesting all through the first series is Harry's unpredictable sinister side, it still surprises and it still has impact and interest. We saw it this week in his fight on the train and it's ultimate conclusion. The down side of that is another (possibly) compelling character goes nowhere though. We've seen a few of those, and yet we keep seeing more of D'arcy than we need, as her story doesn't go anywhere interesting and it's the same gag for her too, over and over.
The show is really going to have to up their game or they'll lose the audience they got from delivering an interesting set up and off beat story telling style. That's not there any more.