It took 4 episodes, bit FINALLY we discover a little bit more about CAT! So far he has been a little one dimensional, and to be honest, he is this way until Season 3, but here we get to see him at his most Cat-like. We see why he is always creeping around the air ducts, and *SPOILERS* the fact he is not the only CAT aboard!

I love the stuff about the Cat arks, and its a real shame that Red Dwarf has not explored the option of meeting the second Cat Ark (the other one flew into a sun) as the prospect of a shipful of them can only make our Cat a fuller character. 

The stuff about Lister being the Cat "God" is always brilliant and I also hope this is explored more in Seasons XI and XII.