While rehearsing for the musical, Harley released the non-album single "Heartbeat Like Thunder" in April 1986, though it was a commercial failure. In June 1986, a newly remixed version of "Irresistible" appeared as a single. Released as the lead single from Harley's forthcoming solo album "El Gran Senor", the single failed to chart. Shortly afterwards, RAK folded and was sold to EMI, leaving the album to be shelved. Later that year, Harley starred as the 16th-century playwright Christopher Marlowe in the musical-drama "Marlowe", which ran in New York and London. Harley's performance was described by one leading critic as "a major and moving performance." During the same period, Harley undertook an English 'A' level course, to which he devoted three hours of study each day. He passed in June 1987 with a 'B' grade.