(1986, Amanda Donohoe, Oliver Reed)
Middle-aged bloke advertises for a female companion to join him on a desert island. No buses on the desert island, but London scenes include Donohoe travelling downstairs on an RT family bus and stepping off:
Two Plaxton Paramounts, the nearer with Worthing Coaches:
Several London Transport AEC Routemasters pass during this scene, also a T-class Leyland Titan:
…and a brief dream sequence returns to the RT (or RTL or RTW):