Caitriona Balfe feels like the "mother hen" of the 'Outlander' cast.

Caitriona Balfe protects her younger co-stars

Caitriona Balfe protects her younger co-stars

The 42-year-old actress has starred in the drama series since 2014, and she's always made a concerted effort to shield her castmates from online criticism.

Caitriona - who stars alongside Sam Heughan on the show - explained: "99.9 percent of [fan interaction] is really just this lovely wave of people being so supportive and telling you how much they like you. Which is, you know, lovely, right? Who could fault that?

"But like anything, there's a small sliver that is kind of criticising or maybe a little intrusive, and of course as human beings it's hard not to sort of catch on to that.

"I think it's one thing when you're as old in the tooth as Sam and I maybe are, but I think when you are talking about young actors who are coming on to a show and who sort of just step into this wave of all of that, it can be quite overwhelming."

Caitriona feels a responsibility to help build a sense of unity and team spirit among the cast.

She told Sky News: "I feel like the mother hen on the show, that I'm very protective of everybody and you want to make sure that everybody is kind of getting on okay with it all."

Caitriona describes the cast as a "very tight-knit gang" and revealed they enjoy spending time together when they're not working.

The actress shared: "Normally we would have dinner parties at various different houses - I love to host everybody over and we would hang out and go out together and I think that's so important.

"We've been really lucky, you know, we really all are a very tight-knit gang and I think it's really important to be supportive of each other."