Ferguson started his career as an actor, before moving into directing. He began directing for the BBC in the 1960s, contributing to television shows such as Z-Cars, The Newcomers, Compact, 199 Park Lane, Out of the Unknown and Doctor Who, for which he directed the serials The War Machines, The Seeds of Death, The Ambassadors of Death and The Claws of Axos. He remained at the BBC during the 1970s, directing various programmes including Quiller and Colditz, before moving to rival network ITV in 1976. At ITV he directed Dickens of London, directed and produced the spy drama The Sandbaggers, Flambards, Airline and The Glory Boys. In 1985 Ferguson began directing for ITV's police drama The Bill and rose to producer in 1988. Ferguson worked on The Bill during “its most popular period” when it switched in 1987 from a series to a “soap-style” twice-weekly half-hour format. Because of Ferguson's success with the programme, Peter Cregeen - the head of series at the BBC - “poached” him in 1989 to become the executive producer of BBC1's flagship soap opera, EastEnders. Ferguson took over from series producerMike Gibbon in the latter part of 1989. EastEnders had come under criticism due to falling ratings and "comic storylines" which many viewers felt were stretching its credibility. According to EastEnders scriptwriter Colin Brake, Ferguson was responsible for bringing in a "new sense of vitality", and creating a programme that was “more in touch” with the “real world” than it had been over the last year. Ferguson altered the way the episodes were produced, changed the way the storylines were conceptualised and introduced a far greater amount of location work than had previously been seen. As a consequence of these changes, a large number of characters were axed in early 1990 as the new production machine cleared way for a new direction and new characters. Among the characters he introduced were the Tavernier family, pub landlordEddie Royle and most notably the Mitchell brothers and their sister Sam — the Mitchells went on to become major long-term characters, among the most popular featured in the programme. At EastEnders Ferguson was responsible for storylines such as the return of runaway Diane Butcher, Mark Fowler's HIV, Mo Butcher's Alzheimer's, Nick Cotton's attempt to poison his mother Dot Cotton, and the murder of Eddie Royle. Ferguson decided to leave EastEnders in July 1991. He remained with the BBC, producing for the popular hospital drama Casualty, before returning to ITV in 1996 to once again direct for The Bill. His last directorial credit for the programme was in 2002.
