As the supposed arbiter of the spirit world clambers through the opening, he slips on the ledge, almost coming a cropper on the street below.
The fact that the performer playing the spiritual con-man is clearly on his knees hanging on to a window at ground level doesn't prevent at least one first-night audience member from gasping audibly at his apparent near miss with gravity.
This incident speaks volumes about this comic meditation on truth and artifice in which suspension of disbelief is subject as much as form.
It's framed around a faux lecture by PhD candidate Jennifer McGeary, who, along with a couple of actors she's hired to illustrate her spiel, takes a step back in time to meet Dr Doyle himself. The fact that her hired help bear a suspicious resemblance to Peepolykus main-stays Javier Marzan and John Nicholson is itself a double bluff in an extended bag of tricks that features Sherlock Holmes, Harry Houdini and the Cottingley fairies.
Orla O'Loughlin's Traverse Company production in association with Peepolykus is a knowingly seasonal parlour room entertainment that looks at a need to believe in ghosts, whether they're real or not. At more than two hours there's probably too much of it, and it could actually do with being somewhat less formal. There are nevertheless some slick sleights of hand at play here, with Marzan, Nicholson and Gabriel Quigley as Jennifer having a magic time in a show in which seeing isn't always believing.