Sub is a one-woman play about the subject of Sado-Masochism, write by new playwright James Mainwaring together with some creative input by the actress Melissa O’Brien, who is making her Fringe debut. The play is excellently written and performed but given the subject matter and the fairly basic terms in which it is described could cause some offence to the more easily shocked. Ms O’Brien captivates the audience from the moment she appears and holds their attention throughout with a display of her fine acting craft, funny at times, full of emotion at others. Certainly well worth checking out, and I look forward to seeing her act ore in the future. ****