Prior to appearing in the soap opera Emmerdale Farm when it began in 1972, he had already appeared in Coronation Street as an old friend of Hilda Ogden, played by the actress Jean Alexander, as well as a sporting serial called United! as the football supporters’ club chairman. Pentelow also appeared in 1969’s notorious gangland series for Granada “Big Breadwinner Hog” as the unflappable Detective Inspector Walker, one of the CID team on the trail of the trendy, up-and-coming gangland boss Hogarth of the title.

The character of Henry Wilks in Emmerdale Farm was a retired Bradford wool merchant, who became a director of Emmerdale Farm when it became a limited company. He also became a joint owner of the village public house – the Woolpack. His partnership with the landlord, Amos Brearly, played by actor Ronald Magill, added a humorous dimension to the soap opera for almost 20 years. Due to Pentelow’s sudden death, the character was killed off in October 1991. He died in the ambulance on the way to hospital from Emmerdale Farm.