Jam is a port of Chris Morris' comedy radio series Blue Jam to the medium of television. The original radio show started being broadcast in 1997 and its TV equivalent in 2000. It's not just a transfer of the general style of the show; the majority of the "sketches" are taken directly from the radio show (sometimes with no changes to the dialogue). It's sometimes possible to tell which are original because they're those which wouldn't work in an audio-only format. An example would be the sketch consisting of two men in underpants shooting each other in the arse.
Though it's often been billed as a surrealist or black comedy, I'd have to say that Morris has pushed so hard for absurdity that there is almost no humour to be found here. I have a similar problem to that which I have with a lot of syndicated comic strips; I can see where the humour is meant to come from, and why other people find it funny, but I'm just not laughing. It doesn't help that a lot of the sketches are based around one joke and go on for far too long. (Case in point: the man who tries to kill himself by jumping 40 times from a one-storey flat instead of jumping once from 40 stories. The joke is a one trick pony, but it goes on for several minutes with the punchline coming in unsubtly at the end.)
It all gets a bit dull after a while. The whole thing is pretty repetitive, with quite a number of themes or motifs making themselves obvious after viewing the series. Children, repairmen, doctors, vets, criminals, armed robbers, security camera footage, kinky sex, amateurish filming, dropped frames, television, and so forth. Jaaaaam took this to new extremes by applying yet another layer of video effects to an already hyperprocessed show. Thought it's often described as a "remix" of the original Jam, it retains the same sketches, the same order, same running times, same ambient music, and so forth. Good if you're in a low-key, sombre mood, but otherwise not really what I'd look for.
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