So you and your family decide to buy a house. You decide on a city, you decide on a neighborhood, you decide on a house, you can afford the house, you like the area, you like the schools, everything’s falling into place except maybe you’re the sort of people that aren’t entirely welcome in the neighborhood you’ve chosen, for some reason or another, because people are often demons. But you really want to live in this neighborhood, in this particular house. What do you do? You could sue, maybe, these days, or say to hell with that place and those people, but if it’s the 1950s and you’re a professional African-American couple and you want to move into all-white Arlington, Mass., you pay a broke Irish-American couple to buy the house on your behalf, in a practice called “ghost buying”, which was sadly very necessary for many years in this country – and may well still be – and is the central plot of Kirsten Greenidge’s new drama The Luck of the Irish, which opens this Friday at the Boston Center for the Arts’ Calderwood Pavilion. (Andrea Shea, WBUR)