Who killed Christopher Marlowe?

Playwright and poet Christopher Marlowe was knifed to death after leaving a house (not a public as is sometimes reported) in 1593 in Deptford. The circumstances were shady. Days earlier a warrant had been issued for his arrest. Was he a spy? He was buried in an unmarked grave in the churchyard of St Nicholas Deptford. A later plaque in his honour can be seen in the churchyard wall. Lewisham libraries has several books on Marlowe if you want to take things further.