A collection of letters from the late British actress and style icon Audrey Hepburn go on auction on Wednesday at Bonhams in London. The series of letters are a correspondence between Hepburn and her acting coach Sir Felix Aylmer during a tumultuous time in her life during the 1950s. The letters are expected to sell for more than $5,000. The auction also includes a notebook that belonged to Freddie Mercury and guitars owned by musician Gary Moore.