Go And See A Man About A Dog
Meaning: To go away and do other things you have to do; to disappear from view for a period of time.
Origins and History: An expression that was coined by Dion Boucicault in his play The Flying Scud (1866) – a horseracing melodrama alternatively titled A Four-Legged Fortune – in order to get an unwanted character (an old and crotchety jockey) off stage.
*From the book Dog the Wag by Mike Darton