I'm not really a shippy fan, but now that you mention it there could be something between them. Perhaps more from Kate's side tho?
In the 2nd eppy I thought she was acting rather strange in some of their scenes together but I put it down to the fact that Kate and Jack were simply suspicious of his motives - and whilst that is still true, perhaps the point was to also convey somesort of attraction?
..and she did try to cop a feel of his booty - she says she was going for the gun, but I don't believe her
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Moved to Shippers forum as it might get more attention there.