She recalls staying at the former St Bathans Police Camp, set up in 1864, where they spent the night in a self-contained former jail cell. Returning from dinner, the couple arrived just in time to stop a fire breaking out.
Tollemache says despite the fact no one else had access to the room, there was no draught - the windows where shut anyway - a light had teetered over the edge of a dresser, landed on a unbelievably awkward angle and the bulb had connected with wallpaper which was starting to smoulder.
Talking to folks at the Vulcan Hotel, reputedly one of New Zealand's most haunted buildings, she says locals shared their own experiences of the supernatural.
"These were people who you wouldn't think were that way inclined but many of them told stories about places they believed to be haunted, rooms in their own homes that they didn't go into or parts of buildings they wouldn't work in."
Within a few days, the honeymoon had turned into a research trip with Tollemache and Ladderman convinced the "tales of terror" would make brilliant theatre. Between them, they'd already made more than 50 shows - performed at home and around the world - and won the Iron Chicken, the World Buskers' Festival's critics' choice award.
But at the Fortune Theatre in Dunedin, after a settled and successful premiere season at the Court in Christchurch, disturbing events started anew. Late one night, while setting up in the Fortune, the couple and a stage manager heard an incessant beeping noise. It turned out to be an old stopwatch that hadn't been used for a year and had been packed away in a box.
No matter what they tried, it wouldn't stop. In the end, it was smashed when the stage manager threw it on the floor in a last-ditch effort to get it to be quiet. They put it in the car and drove home.
"But the next day, the car wouldn't start," says Tollemache.
"The head gasket was completely blown, even though there'd been no warning or prior trouble with the car. We couldn't get it fixed; the car never started again. We had it taken to a wrecker's yard - with the stopwatch in it."
It means The Dunstan Creek Haunting is a mix of historical legend, local folklore and their own experiences. They say it will appeal to fans of The Conjuring and The Others and that it's not for the faint-hearted.
Tollemache agrees getting horror right in the theatre is a balancing act, often heavily dependent on good sound effects. She's grateful for time spent in London where the couple saw as many ghost stories as they could.
"We realised that when a audience gets a fright, there's a moment afterwards when everyone starts giggling; it's sort of like an involuntary reaction. Had we opened our show and not realised that, we would have been completely thrown."
The show is R13 but for those with kids who are fascinated by things that go bump in the night, Tollemache and Ladderman stage Halloween; Trick or Treat (Saturday and Sunday). It's created especially for ages five and upwards with just the right amount of spooky without causing nightmares.
Lowdown:
What: The Dunstan Creek Haunting
Where & when: Herald Theatre, October 24-31
(producers Auckland Live and Rollicking Entertainment advise the show is R13)