One scene features Dennis Dart/Carlyle Dartline WLT881 in allover red livery. The Dartline was designed by Duple, but the design was sold to Carlyle when Duple were bought by Plaxton. This is one of a batch of Darts built for London Buses as their DT class. The first handful were Duple; this is one of the Carlyle ones. It's DT88, its original registration was H588MOC, but in 2001 White Rose of Thorpe, who then owned it, transferred the registration from RML881 onto it, hence the WLT881 registration plate. Another scene has an open top Leyland Titan TN of the Big Bus
Company sightseeing operation (thanks Gavin Rowney)