Caitriona Balfe feared she'd reveal Outlander secrets during dental surgery

Caitriona Balfe was a little worried her anaesthesiologist would try and get Outlander secrets out of her during a recent dental surgery.

As part of an appearance on The Late Show with Stephen Colbert on Wednesday night, the Irish actress discussed the pressure she is under to keep details about the popular historical drama series under wraps.

However, Caitriona admitted that she was concerned that the doctor may try and inveigle secrets while she was under anaesthesia not so long ago.

"There can be interesting moments, I'd say. I recently had to undergo anaesthesia because I had to have dental surgery. I get to the place and the anaesthesiologist comes in and she had an Outlander mug and was like, 'I'm your biggest fan!' And I was like, 'Oh this is good, she's really going to take care of me,'" she remembered. "But then, we went in and she was telling me how she was going to put me under and was asking me questions about the series and what was going to happen. And I was like, 'I'm not supposed to tell you stuff!' Then, when she injected me and I was lulling off, she started to sing the theme tune. I was like, 'Nooo!'"

Caitriona went on to describe the moment as one of the "stranger interactions" she has had with a fan, and joked that she had been imagining a scenario where she "was going to be in her basement with all the Jamie (Sam Heughan) posters everywhere."