Sam Heughan and Caitriona Balfe were being heavily shipped by “Outlander” fans after seeing their undeniable chemistry on-screen. However, despite their connection on and off the set, the “Outlander” actor is actually very much taken by another actress, "Into The Woods" star Mackenzie Mauzy.

Caitriona Balfe seemingly ended all romance rumors with her co-star by sharing a photo of her with Sam Heughan and Mackenzie Mauzy on social media during the actor’s 37th birthday. The “Outlander” actress proved that there is definitely no bad blood between her and Sam’s real-life lady love.

But, just because Sam Heughan is already taken, doesn’t mean that he and Caitriona Balfe will stop being close friends. The “Outlander” season 3 co-stars have been exchanging tweets, and their recent tweets caused another stir as some people may have taken it as being sweet, funny, but flirtatious at the same time.

'Outlander' stars reveal relationship status in recent post

Sam Heughan took to Twitter to share that Caitriona Balfe may have been thinking about his character (James "Jamie" Mackenzie Fraser) as the 37-year-old Irish actress and model called out his name while fast asleep. Zzz zzz......"FRASIER"!......zzz zzz z,” the actor tweeted.

Although the actor did not mention any names, it seems like Caitriona Balfe was the guilty one, as she responded to her co-star's post and said, “"I'll see your Zzzzz and raise you ZZZZzzzzzzzzzzzzzzzzz.” The stars have been filling up their posts with “zzz’s," alluding to the fact that their busy schedules are causing them to be sleep deprived.

Although people may find their friendship to be very close, Sam and Caitriona's conversations were posted on a public platform, proving that they are not hiding anything romantic at all. But, despite multiple denials, speculation of them taking their working relationship to the next level are always being talked about. Due to the fact that they are such a believable couple on-screen, shippers are constantly shipping the pair in real life as well.

'Outlander' co-stars more than friends?

One report revealed that Sam Heughan and Caitriona Balfe were allegedly holding hands on set. "Sam and Caitriona were taking a short break between scenes when I saw them off to the side, holding hands, and Sam was even whispering in her ear," a source told Celeb Dirty Laundry.

Despite these allegations, the "Outlander" season 3 co-stars have noted that they are just friends and nothing more.