The paintings in Harrison's BA degree show at Chelsea School of Art in June 1987 were noted for their apocalyptic presence and rich and varied paint handling. In August 1987, Harrison was selected by the
London Evening Standard's art critic
Brian Sewell for "Young Masters". Harrison's contribution consisted of figures engaged in titanic struggle and landscapes in immense flux. In a review of Harrison's first solo show in 1990 at the Berkeley Square Gallery in London's Mayfair, Sewell wrote that Goya, Rembrandt and Delacroix might recognise him as in some sense their heir. In 1993, Harrison's next solo show was at Jill George Gallery in London's Soho, and he then had solo shows at
Albemarle Gallery in London's Mayfair in 2002, 2003, 2006, 2008, 2010, 2013 and 2016, and at Pontone Gallery in 2018, 2022 and 2025. The landscape paintings in the 2006 Albemarle Gallery show were likened to a Götterdämmerung, and The Horsemen in the same show were said by Sewell to be the product of a darkly mediaeval imagination. In 2023, Harrison had his first New York solo exhibition at Friedrichs Pontone in the Tribeca district of downtown Manhattan. In 2010, Harrison was selected for the
John Moores Painting Prize Exhibition at the
Walker Art Gallery in Liverpool. In 2011 he had exhibitions at Dea Orh Gallery in Prague, Czech Republic and at Chenshia Museum in Wuhan, the first exhibition by a British artist in a private museum in The People's Republic of China. On 22 January 2009 his monumental crucifixion triptych “At The End … A Beginning” was installed and consecrated in the ambulatory behind the high altar in
Liverpool Anglican Cathedral. A second crucifixion, "Golgotha", hangs in London's oldest parish church, The Priory Church of St. Bartholomew The Great near Smithfield Market. == Style and influences ==