"In the 118 tour it's just not feasible to have all the extra installations so we've really taken the spirit of those stories into the show."

The Birthday Tour is described as a promenade piece in which audiences are taken around the venue buildings (and even onto a bus). Structure is suggested by the theme of a birthday party, beginning with a lecture-style format in which one of the founder members, Mark Lang introduces the history of the company. "You will go on a mysterious and magical journey", says Cook when I ask her to describe the experience of being in the audience, "Come across all sorts of interesting characters who will tell you their stories. Witness lots of unusual sights, and hopefully think it's a jolly good show."

So do you still think that you're on the margins of the establishment? I finish. "Well we're an extremely modest company," Sadie answers. "We've always been concerned with making new stuff, we've never really capitalised on touring old work". She laughs. "Of course we’d have made more money doing that. And it would be good if more people knew about us. But I love the fact that every show is totally different."

The Birthday Tour 118 tours until the middle of April and then the company will start researching their new project - a site-specific work at the glass Palm House in Liverpool. ER