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. In 1988, Batt approached Harley to provide vocals on his song "Whatever You Believe", alongside Jon Anderson. On 3 May 1988, the trio performed the song at a live TV broadcast at Battersea Park in London, as part of the Thames/LWT charity fundraising effort for the ITV Telethon. Later in November, a studio version was released as a charity TV tie-in single under the name Anderson, Harley & Batt. It did not chart. Following its use in a successful TV advert for Trebor Softmints, "Mr Soft" was re-issued as a single in 1988, but also failed to chart. In 1989, Harley assembled a new line-up of Cockney Rebel and embarked on a comeback tour named "All is Forgiven". The tour was a success, which led Harley to continue performing with various incarnations of Cockney Rebel throughout the 1990s and beyond. To promote the 1989 tour, Harley released the solo single "When I'm with You", which had been recorded before the tour with ex-Cockney Rebel members Duncan Mackay and Jim Cregan at London's Point Studios. Later in October, a VHS using concert footage from the tour was released under the title "". In late 1989, Harley was scheduled to play the title role in a feature film based on the true story of John 'Babbacombe' Lee, an Englishman famous for surviving three attempts to hang him for murder. However, the film never raised the necessary funding and the project was cancelled in the early 1990s. Throughout 1989 and 1990, Harley continued recording material and working on a new album. During 1990, Harley also contributed to the album "Poetry in Motion" by providing lead vocals on the track "Harrow on the Hill". The album consisted of fourteen tracks featuring the words of Sir John Betjeman and music by Mike Read. In October 1991, Harley was invited to play Night of the Proms, where he performed "Sebastian" and "Make Me Smile". Harley's solo album "Yes You Can" was released in Europe in 1992 and the UK in 1993.