Spooner and Dalek creator Terry Nation. A few episodes were credited to Tony O'Grady, a pseudonym of The Avengers writer-producer Brian Clemens. The character of Mannering was, like Simon Templar in The Saint, a member of the jet set, whose glamorous lifestyle was typified by air travel to exotic locations, which at the time was still only easily available to the wealthy. However, filming never left the UK; it was filmed chiefly in and around Elstree Studios in Borehamwood, Hertfordshire, then owned by Associated British Pictures. Locations used included Haberdashers' Aske's School in Elstree, St Albans and Ivinghoe Beacon. These featured prominently in several other ITC series of the same era. The backlot at Elstree in particular was extensively used, being transformed alternately into Mannering's antiques shop, a Mexican town, a Parisian nightclub, an East European police station and many others besides. Paul Ferris was originally cast as Mannering's assistant David Marlowe. However, after pressure from the US network ABC, Marlowe was dropped in favour of the more glamorous Cordelia who had appeared in the first episode. She is 'reintroduced' in "Something for a Rainy Day", the ninth episode to be made, although broadcast third. As originally broadcast, the 'Cordelia' and 'Marlowe' episodes are interspersed, even though Paul Ferris left the production after eight episodes were filmed. As with other ITC series, the American market was vital; several episodes were overdubbed (e.g. "petrol" becoming "gas", "whisky" becoming "Scotch") to ensure they were fit for US audiences. Roy Ward Baker stated that owing to US sponsorship by a cigarette company, characters "were allowed to light up only in moments of leisure, never when they were frightened or under duress". The show did not do well enough on ABC and was syndicated midway through its run, which effectively ensured that no second series would be made. The Baron's car was a silver Jensen CV-8 Mk II with the registration BAR 1. Unlike the Volvo driven by Simon Templar, the exclusivity of the car meant the series did not generate the same sales boost as The Saint had done for Volvo. Cordelia drove a considerably less upmarket DAF Daffodil 33. The episode "Something for a Rainy Day" featured shots of a white Jaguar plummeting over a cliff. This footage, apparently filmed for this episode (from several angles), reappeared in several other episodes and series, in an attempt to render its high cost worthwhile.