Tupper appeared in the beginning of this season as trauma counsellor Andrew Perkins, who began a romance with Teddy (Kim Raver).
Speaking to TV Line, Tupper explained that Andrew will want to continue the relationship when he comes back to Seattle Grace Mercy West.
"He's a bit nomadic, he's travelling, and he's back in town when he contacts her," Tupper said. "They liked each other before, so they're trying [a romance] again."
Tupper, who explained that Teddy will keep her marriage to Henry (Scott Foley) a secret, also hinted that the relationship between Teddy and Andrew will begin to develop.
"I do make her a proposal," he teased. "I'm waiting to see [what happens] just like you are, but I think there's a chemistry there."
Grey's Anatomy returns for a new episode in the US on Thursday at 9/8c on ABC. The show continues in the UK on Wednesdays at 10pm on Sky Living in the UK.
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