Then as the bow sinks, it pulls the stern vertical and then finally detaches.

8 seconds sound clip from the Titanic (1997) movie soundboard.

You can hear this line at 00:18:20 in the Blu-ray version of the movie.

Quote context

[...]

- She kind of bumps along punching holes like Morse code dit-dit-dit along the side below the water line. Then the forward compartments start to flood.

- Now, as the water level rises, it spills over the watertight bulkheads which, unfortunately, don't go any higher than E deck.

- So now as the bow goes down the stern rises up, slow at first then faster and faster until finally, she's got her whole ass sticking up in the air.

- And that's a big ass. We're talking 20, 30000 tons. Okay?

- And the hull's not designed to deal with that pressure. So, what happens? She splits, right down to the keel. And the stern falls back level.

- Then as the bow sinks, it pulls the stern vertical and then finally detaches.

- Now the stern section just kind of bobs there like a cork for a couple of minutes, floods, and finally goes under about 2:20 AM

- 2 hours and 40 minutes after the collision.

- The bow section planes away, landing about a half a mile away going 20, 30 knots when it hits the ocean floor.

- Pretty cool, huh?

[...]