Jaws and the USS Indianapolis

In Jaws, the character Quint (Robert Shaw) explains some of his history on the boat as he (and the two main characters, played by Richard Dreyfuss and Roy Scheider) are Jaws hunting.

whysanity.net/monos/jaws
lists the exchange

written by Peter Benchley & Carl Gottlieb

Hooper (Richard Dreyfuss): You were on the Indianapolis?
Brody (Roy Scheider): What happened?
Quint: Japanese submarine slammed two torpedoes into our side, chief. It was comin' back, from the island of Tinian Delady, just delivered the bomb. The Hiroshima bomb. Eleven hundred men went into the water. Vessel went down in twelve minutes. Didn't see the first shark for about a half an hour. Tiger. Thirteen footer. You know, you know that when you're in the water, chief? You tell by lookin' from the dorsal to the tail. Well, we didn't know. `Cause our bomb mission had been so secret, no distress signal had been sent. Huh huh. They didn't even list us overdue for a week. Very first light, chief. The sharks come cruisin'. So we formed ourselves into tight groups. You know it's... kinda like `ol squares in battle like a, you see on a calendar, like the battle of Waterloo. And the idea was, the shark would go for nearest man and then he'd start poundin' and hollerin' and screamin' and sometimes the shark would go away. Sometimes he wouldn't go away. Sometimes that shark, he looks right into you. Right into your eyes. You know the thing about a shark, he's got...lifeless eyes, black eyes, like a doll's eye. When he comes at ya, doesn't seem to be livin'. Until he bites ya and those black eyes roll over white. And then, ah then you hear that terrible high pitch screamin' and the ocean turns red and spite of all the poundin' and the hollerin' they all come in and rip you to pieces.
Y'know by the end of that first dawn, lost a hundred men! I don't know how many sharks, maybe a thousand! I don't know how many men, they averaged six an hour. On Thursday mornin' chief, I bumped into a friend of mine, Herbie Robinson from Cleveland. Baseball player, bosom's mate. I thought he was asleep, reached over to wake him up. Bobbed up and down in the water, just like a kinda top. Up ended. Well... he'd been bitten in half below the waist. Noon the fifth day, Mr. Hooper, a Lockheed Ventura saw us, he swung in low and he saw us. He'd a young pilot, a lot younger than Mr. Hooper, anyway he saw us and come in low. And three hours later a big fat PBY comes down and start to pick us up. You know that was the time I was most frightened? Waitin' for my turn. I'll never put on a lifejacket again. So, eleven hundred men went in the water, three hundred and sixteen men come out, the sharks ttook the rest, June the 29, 1945. Anyway, we delivered the bomb.

The story of the USS Indianapolis is a true and tragic one.

For detailed info on the fate of the USS Indianapolis see ussindianapolis.org and discovery.com/exp/indianapolis