*** 19*** Scientists have discovered a massive lake in the arctic beneath a mile of ice. When they send down an exploratory team (including your character), the sonar and other navigational equipment begins to pick up strange signals. Just out of reach of the seacraft's lights, something enormous looms.
Grant, Laura (2012-05-31). 101 Writing Prompts for Fantasy and Science Fiction Writers, vol. 1 (pp. 17-18). Desk & Chair. Kindle Edition.
Joey Maguire thought that maybe he should have stayed on the streets instead of going to school to become a marine biologist.
Whenever he got himself into these tight situations, he always blamed Father Fitz, his mother, and his absent father. He blamed the college, the boss, the captain, anyone but him. Anyone.
Except the pilot of the seacraft. "Do you see what I see, Unger?" Maguire asked him, as the light caught what he thought was a dome of coral. Underneath the dome was...buildings?
"Can't be. It can't be." He leaned forward in his seat.
"What's down there, Unger?" yelled the captain into their ear.
"Domes. With buildings."
"Come back around, we can't see --"
There was a roar, even in the water, and something smacked the side of the mini-sub, sending it tumbling sideways. Klaxons and alarms went off as Maguire cursed and prayed at the same time. Unger tried to right it, and then it got hit again, from the aft side. Engines screamed as Under pulled to get it right, and they were heading straight for a rock.
They smashed into the rock, and the pressure let go, water started leaking from the top. They tried to get into their scuba gear, but Unger shoved Maguire aside and took up most of the room. All Maguire could do was grab a tank and get that on him, no flippers, no nothing. He was going to freeze if he didn't drown.
Unger undid the top and in his panic, shoved open the shaft, water cascading into the sub. Unger kicked out, and Maguire wanted to send him off with a hearty "Fuck you, too, asshole."
Then suddenly, there was blackness around him. He looked up to see Under being sucked away, and he stayed in the mini-sub, choosing to die inside here than attempt to freeze out there.
Holy Mary, Mother of God, pray for us sinners...
He was jolted back and forth around inside the minisub, like something had shaken it. He hit his head on something and was blessedly passed out. I will die quietly.