MacCorkindale was born in Cambridgeshire, England to Peter and Gill MacCorkindale. He has a younger brother, Duncan.

He has a vast number of acting credits to his name having appeared in numerous television and film roles both in United Kingdom and America. These include Hammer House of Horror - Visitor From The Grave, Beasts, The Sword and the Sorcerer, Death on the Nile, Quatermass, Falcon Crest, The Riddle of the Sands and Jaws 3.

He served as the male lead on at least two television programs: Manimal in 1983 and Counterstrike from 1990-1993. He has also stared in At The Midnight Hour with Patsy Kensit. MacCorkindale is also an acclaimed stage and television director and producer, and has his own production companies, Anglo Films International and Amy International Artists.

He made his TV directing debut in 1986, directing the Falcon Crest episode "Checkmate". He served as co-executive producer for the 2000 syndicated TV series Tessa, Queen of Swords and the 2002 syndicated Canadian TV series Adventure Inc.. He also produced and composed music for the 1989 film Djavolji raj (That Summer of White Roses), starring his wife Susan George.

MacCorkindale joined the cast of the BBC One medical drama Casualty and portrays clinical lead consultant Harry Harper. In February 2007, MacCorkindale took a sabbatical from Casualty to tour the UK in a revival of the Agatha Christie thriller The Unexpected Guest.