We're gonna need a bigger budget. Steven Spielberg's Jaws went on to invent the summer blockbuster, alongside Star Wars from his pal George Lucas, which arrived two years later. But Jaws began as a troubled production that went way over budget and made Spielberg fear for his job. Here we'll take a look at 10 things you never knew about Jaws.

A shark by any other name.

Perhaps some of the best-known behind-the-scenes trivia from Jaws is the nickname the cast and crew gave to the 25-foot great white shark at the movie's center, which was played by three full-scale mechanical models. Bruce. Yes, Bruce. The nickname was a good-natured tribute to Spielberg's lawyer, Bruce Ramer, who has represented the filmmaker for decades. Clint Eastwood and Robert Zemeckis are also longtime clients. After numerous malfunctions resulted in repeated production delays, Spielberg devised another nickname for the shark, too: the Great White Turd.

The famous score.

Who hasn't sat down at a piano at some point and tapped out the sinister two-note theme from Jaws, a deceptively simple piece of music filled with dread and foreboding? Well, the first time composer John Williams tickled it on the ivories in front of Steven Spielberg the director thought he must be joking. The director would later credit the theme with much of the movie's success. Jaws marked the second collaboration between Spielberg and Williams and but one of the composer's many famous themes which include Star Wars, Superman: The Movie, and Indiana Jones.

The other Chief Brodys.

Roy Scheider, who improvised the film's most famous line ("we're gonna need a bigger boat"), actually wasn't the producers' first choice for Chief Martin Brody. Among those courted were Robert Duvall, who reprised his role as Tom Hagen in The Godfather Part II the year before Jaws, and screen legend Charlton Heston.

The other Captain Quints.

Robert Duvall wasn't the only Godfather cast member who could have been in Jaws. Sterling Hayden, who played corrupt Irish-American cop Captain McClusky in The Godfather, was offered the role of Captain Quint. Before Robert Shaw was cast, producers also went after World War II veteran Lee Marvin, famous for playing various hardboiled soldiers, cowboys, and police detectives in film and television.

The other Matt Hoopers.

Before Richard Dreyfus was cast as marine biologist Matt Hooper, there were discussions with Jeff Bridges, who starred in 2010's Spielberg-produced True Grit. The studio also reportedly wanted Jan Michael Vincent, but Spielberg fought for Dreyfus, 'though he had to do much convincing of the actor himself along the way.

The shrunken shark cage.

A second unit captured real footage of sharks off the coast of Australia. But since the sharks were much smaller than the movie's title villain, they used a deceptively smaller shark cage, with a wetsuit-clad 4 foot 9 former jockey standing in as Hooper.

Speaking of real sharks...

The production flew in a 13-foot tiger shark caught off the coast of Florida to use for the scene where the townspeople string up a shark on the dock thought to be the shark. The real life locals were unable to catch a shark that big, but flying one in had its problems, too. By the time they were filming, that shark corpse was going rotten.

Hooper's love affair.

In order to keep the story lean and mean, Spielberg tossed out different subplots from the source material. In the novel, Hooper has an affair with the chief's wife, Ellen, played by Lorraine Gary, who returned for Jaws 2 and Jaws: The Revenge.

Hooper dies in the book.

The love affair for the Richard Dreyfus character may have been cut but so was his death. Hooper's death in the book made it into the script, but not the finished cut. That second unit in Australia captured fantastic footage of the sharks attacking the empty shark cage, so Hooper was allowed to escape in the film so they could make use of it, rather than having the shark bite through it and kill him as planned.

A few more differences...

There are a number of other changes from the book. Here are a few of them: Amity is a town in Long Island in the book, not New England. Brody is a local, not an outsider. The Brodys have three kids, not two. Quint gets his leg caught in a harpoon rope and drowns. The shark dies of exhaustion, rather than from an explosion.

We hope you learned something from this look at 10 Things You Never Knew, or at least maybe never knew, about Jaws. There are a number of great Jaws documentaries out there to satiate your shark like craving for more information about the endlessly re-watchable blockbuster thriller. Like many Reddit users, we highly recommend The Shark is Still Working.

The documentary is a labor of love from J. Michael Roddy, who helped create JawsFest on Martha's Vineyard. It includes sit-down interviews with Spielberg, Dreyfus, John Williams, the late David Brown and Richard Zanuck, and the last interview with author Peter Benchley before he passed away. Scheider even offered to narrate, recording all of his parts just a few months before he died. Jaws loving filmmakers in the doc include M. Night Shyamalan, Kevin Smith, and Bryan Singer.