'Batwoman' Finale Sneak Peek: Alice and Mouse Don't See Eye to Eye on Their 'New Life' (Exclusive)

ET exclusively debuts a first look from Sunday's freshman finale.

Trouble in "sibling" paradise?

Batwoman wraps up its freshman season on Sunday with its makeshift finale, titled "O, Mouse!," and in ET's exclusive sneak peek, there is major tension between Alice (Rachel Skarsten) and her "brother," Mouse (Sam Littlefield), who aren't seeing eye to eye on their next move.

See, Alice is dead set on finding a solution to take down Batwoman (Ruby Rose) for good, but Mouse is ready to pack up and leave Gotham for good, especially with Gotham P.D.'s new Crows app that would make it very easy for anyone with the app to turn them over. It's during their conversation that Mouse realizes the promise she made -- that they'd be able to start "a new life" outside Gotham -- just isn't going to pan out the way he hoped.

"We gotta get out of Gotham, Alice," Mouse pleads, as a scurry of bats blast through. He reminds Alice that they're not exactly at the top of the food chain at the moment, telling her that they're "rats living among rats." "You promised me that we would start a new life together outside of all this, but we can't do that if the Crows find us and kill us." 

But Alice just can't let go of the past, not until she can find the elusive kryptonite that will bring Batwoman to her knees.

"How is one supposed to start anew when all that is old still haunts her?" she asks. "Is that the Alice you want to frolic beside in our wonderland or do you wish your Alice to be full and complete and happy?"

"You know that's what I want," Mouse says in desperation, clearly unhappy with the way the chat is going.

"Then patience," Alice replies, flipping through pages of Lucius Fox's journal for clues on where to find the kryptonite.

But they're sorely interrupted when an angry Hush (Gabriel Mann) rushes in to their underground lair and he has a lot on his mind. Watch ET's exclusive sneak peek above to see what happens next.

The Batwoman season finale airs Sunday at 8 p.m. ET/PT on The CW.

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