Sam shared the image in question to his profile, which doesn't appear to have been taken at any of the BATG filming locations. The background actually looks like Sam or Tegan's home.
Both wearing big smiles and a filter that left hearts on their cheeks, Sam captioned the photo: "Another classic Saturday night."
Moments later Tegan replied "We're cute. Love you thammy," with two kissing emojis.
Fans quickly cottoned on to the flirty exchange, one commenting: "Oooh has there been a partner swap already?"
WATCH: Sam and Angelique kiss on Beauty And The Geek. Story continues.
A little digging on Instagram revealed that Sam and Tegan are both following each other and have liked all of one another's posts from Beauty And The Geek.
Currently all of the cast's Instagram accounts appear to be managed by the BATG team, but in the months between filming and the show's premiere they seemed to have control over their posts and likes.
Tegan dropped a like on one of Sam's from June, before the show went to air, while Sam liked a stunning snap of Tegan in a glittering dancing outfit just before the show premiered.
Though it doesn't prove anything, the two have certainly been staying in touch since filming wrapped.
But what about Sam's on-screen romance with Angelique?
Though they've both been liking each other's BATG posts, Angelique has yet to drop a like on Sam and Tegan's cute selfie.
Again, a few Instagram likes (or lack thereof) doesn't prove anything but fans think the new selfie from Sam and Tegan suggests he and Angelique may no longer be together.
"Honestly I couldn't have asked for anybody better. She was the best partner. I love her so much," he told Now To Love of Angelique exclusively last week.
But he quickly added on a cryptic comment that is starting to make more sense.
"I won't go into too much detail because I want everyone to see it when it comes out... but we do still talk a lot. It's still very good," Sam said.
Could he have been hinting that he and Angelique called it quits only for him to find new romance with Tegan?
It looks like we'll just have to wait for the BATG finale – where all the contestants return – to find out the truth.
This article first appeared on our sister site, Now to Love.