I remember (roughly) where and when I watched it for the first time, back in early 92, with an ex after a weekender living up in central Manchester, during my student days...
which undoubtedly helped set the right mood for watching it. Gritty, urban and living alongside a fairly heavy drug gang culture locally. Nee aliens though, well some pyschedelic ones sometimes
Not sure what I'd think if I watched it now....
.just started watching "Them" on Amazon. It's a creepy as **** series - kind of a cross between stepford wives/the shining/ Mississipi burning!