He was educated at King Alfred School, London and the University of Sussex where he studied philosophy, graduating in 2004. As a schoolboy he played Colin Craven in the 1993 film The Secret Garden.
For the United Kingdom general election, 2015, Prowse changed his name to Michael Green via deed poll in order to stand as an independent candidate against Grant Shapps in the Welwyn Hatfield constituency. The name Michael Green is a pseudonym of Shapps which has attracted controversy. He secured 216 votes in the election, placing sixth out of seven candidates.
- "BBC3 announces new entertainment commissions". Televisual. Retrieved 16 May 2014.
- "From angel to activist: Heydon Prowse". London Evening Standard. Retrieved 16 May 2014.
- "The pranksters who gave George Osborne a GCSE maths book". The Guardian. Retrieved 16 May 2014.
- "Secret Garden actor turns into a green campaigner". London Evening Standard. Retrieved 16 May 2014.
- Burke, Dave (29 April 2015). "Satire show comic is standing against Grant Shapps after changing name to Michael Green". Welwyn Hatfield Times. Retrieved 29 April 2015.
- Crace, John (29 April 2015). "A la Recherche du Shapps Perdu … or anyone seen Grant Shapps?". The Guardian. Retrieved 1 May 2015.
- Metcalfe, Neil (8 May 2015). "General Election 2015: Welwyn Hatfield result". Welwyn Hatfield Times. Retrieved 9 May 2015.