Sexy, Italian-designed chopper favoured and used by THEM. THEY got a taste for this particular type when they captured a couple off the Argentineans during the Falklands Conflict. So impressed were they with the aircraft's performance that they blagged them.
The type offered 'Them' a certain level of anonymity, being noticeably less military looking than the type previously used - the Scout. Though more ally-looking, the Scout was considerably slower and noisier, with a much reduced carrying capacity. The adoption of the A109 solved this problem.
The two original Argie bring backs are still in use, but such is the allure of 'Them' that they managed to convince the MoD to buy them a couple more to play with. These are operated by the shadowy 8 Flight at Credenhill and are all finished in unobtrusive civvy schemes so as not to look too obvious when hovering over a foreign embassy roof, disgorging a string of troopers in full black rig... like yer do.
The 109s are soon to be replaced by Dauphins.