The TV adaptation of Len Deighton's trilogy was aired in the UK in the autumn of 1988. It is notoriously difficult to get hold of, though apparently the original producers, Granada, will run off a copy at a VERY expensive hourly rate. The adaptation is not actually available as a UK release, as it was never released on video at the time, so buying it now is exceptionally difficult.
The Internet Movie Database page http://www.imdb.com/title/tt0092360/ has more information on the cast etc.
I, however, have seen the whole thing in full. It's a very true adaptation, in that it deviates very little from the original source and is highly watchable as a result. Some of the casting left me wondering, but on the whole I was impressed. In my opinion, not enough was made of the allure of Tessa and the differences between her and cuckolded husband George. Dicky Cruyer is not as annoying as he should be, though the vast majority of the characters are eerily close to how I imagined them.
The big question is "Where do I get it?" Well, with great difficulty. It's one of the toughest big adaptations to get, but I got around this by going to the British Film Institute. They hold it in their archives and you can, for a fee, go and see it.
You can, however, buy a copy from Granada. This would be exceptionally expensive at £198 (Sterling) per episode. There are 13 episodes so you'd be looking at £2,574 for the full set!
This information is direct from Granada. Thanks to Efrat in Israel for this one as he did the leg work after I suggested contacting Granada. The contacts page for Granada is:
http://www.granadatv.com/corporate_info.php?region=Granada&content=15
The upside of paying the BFI is that you don't have to pay Granada £2,574 or so to make you a copy, but the BFI will charge £10 a viewing hour + VAT. This fee is halved for students. The archived copy is a recording of that evening's television, so you even get the adverts!
The BFI's collections link http://www.bfi.org.uk/collections/ will give you an opportunity to email them about it. I can verify, however, that it can be done and I have seen it, so if you are a real Deighton fan and don't want to miss out, you can give it a go.
I often get requests from people outside of the UK, but as far as I know there is no way to get to see the series out of the UK - if anyone knows of a way then please let me know.