If you've been waiting for the powder keg that is Kate (Ruby Rose) and Sophie's (Meagan Tandy) relationship on Batwoman to finally explode, we highly suggest you tune in for this Sunday's episode, titled "Tell Me the Truth." Not only do we have a pretty hefty amount of relationship drama on tap (both past and present), we also have that pesky little problem of Sophie knowing that Kate is Batwoman to deal with.

"Sophie has been trying to figure out whether Kate is Batwoman or not, and she's definitely feeling more confident now that she is because, in the previous episode, Kate put her hand right up on [Sophie's] lips just like she did in the pilot," Tandy told TV Guide. "So she's of course conflicted — does she tell Commander Kane (Dougray Scott) or not? But she also wants to protect Kate, so it's a difficult situation."

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Given that the chemistry from the lip-shush in the pilot nearly exploded right off the screen, it's easy to understand why Sophie would take that otherwise innocuous gesture and turn it into foolproof evidence that Kate is donning a red wig and taking to the skies every night. You can't fake that kind of connection, right? Although it's obvious the connection is still there for Kate, it's been harder to pin down in Sophie's case. Has she really moved on to a happy life of marital bliss with her husband, or are feelings still lingering on both ends?

"I think it's a two-way street," Tandy said. "I feel like if it were not, she probably wouldn't be so concerned about not only Kate's safety, but I feel like there wouldn't even be an issue at all. Like, 'I'm married now, bye!' But instead, it's kind of like — if you saw in the pilot, she ... felt remorseful for having had this husband when this is like the love of her life. So I think she's trying to figure it out."

Meagan Tandy and Ruby Rose, <em>Batwoman</em>Meagan Tandy and Ruby Rose, Batwoman

Everyone knows the best way for a character to figure out how they feel about a past relationship is via the use of flashbacks, so expect plenty of those in Sunday's episode. We'll get a better picture of what Sophie and Kate's relationship was like in military school as well as what led them to make different decisions about whether to confess to having a relationship or not.

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The blasts from the past don't stop there, though. We'll also get to meet the daughter of iconic Batman character Alfred Pennyworth, and wouldn't you know it, she seems to be tangled up in Kate's past too!

"Julia comes right on into Gotham City," Tandy teased. "She's on a mission, herself, but I think people will be curious to see that she does have a past as well with Kate. In what way you'll just have to tune in and see, because their past actually got ignited because of [Sophie's] decision to no longer be with Kate."

Batwoman airs Sundays at 8/7c on The CW.

(Disclosure: TV Guide is owned by CBS Interactive, a division of CBS Corporation.)

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Melissa Benoist, Brandon Routh, Stephen Amell, Ruby Rose, Chyler Leigh, Grant Gustin, David Harewood, Jesse Rath, Audrey Marie Anderson, Katherine McNamara, Caity Lotz, Tyler Hoechlin, and Elizabeth Tulloch, <em>Supergirl</em>Melissa Benoist, Brandon Routh, Stephen Amell, Ruby Rose, Chyler Leigh, Grant Gustin, David Harewood, Jesse Rath, Audrey Marie Anderson, Katherine McNamara, Caity Lotz, Tyler Hoechlin, and Elizabeth Tulloch, Supergirl