I didn’t realise that noticing the weird resemblance between Roger Allam and Christopher Hitchens was a new thing.  When I watched V for Vendetta years ago, and I saw Allam playing a sleazy, fascist, corrupt talk-show host I briefly assumed that Hitchens had volunteered to do a cameo.  Then I discovered that it was a different person, but you can see why I was confused.  The style of argument, the mannerisms, and the personality were all as you would expect.