With three months still left in 2015, it has already been a record year at the box office for Universal Pictures. The studio has become the first in history to have three movies gross over $1 billion worldwide in the same year, Furious 7, Jurassic World and Minions, which contributed to the studio's record-breaking overall gross of $6.3 billion this year. The studio is already moving forward with Jurassic World 2, set for release on June 22, 2018, but a new report from The Hollywood Reporter reveals they are having problems with their Furious 7 follow-up, Fast & Furious 8. The studio has already set an April 14, 2017 release date, but this report claims that they are having trouble finding a director, with Vin Diesel said to be at least partially at fault for the directorial vacancy.

Universal had originally contracted Furious 7 director James Wan to direct Fast & Furious 8 and the ninth installment as well, but before Furious 7 completed production, the filmmaker informed the studio that he wanted to make The Conjuring: The Enfield Poltergeist instead. While Universal accepted his decision, they tried to bring back filmmaker Justin Lin, who directed The Fast and the Furious: Tokyo Drift, Fast & Furious, Fast Five and Fast & Furious 6. However, he decided to take the helm on Star Trek Beyond, which lead the studio to go back to James Wan, offering him what is described as "life-altering money."

This report claims that James Wan turned down the studio's offer for Fast & Furious 8, because Furious 7 was so demanding that it compromised his health. At the heart of this reportedly-traumatic experience was franchise star and producer Vin Diesel, who was said to be "extraordinarily difficult." This is on top of what was an already-troubled production, following the tragic death of Paul Walker, which required extensive rewrites of the script, reshoots and the use of the late actor's brothers to fill in as body doubles. Vin Diesel reportedly questioned the tiniest of details, often holding up the complex production, summoning the filmmakers for late-night script sessions to craft new dialogue that he was comfortable with.

Related: Fast & Furious 9 Brings Michael Rooker Into the Family

However, Vin Diesel's rep called these reports of the actor being difficult to work with, "complete nonsense." James Wan's rep also denied claims of friction between the filmmaker and Vin Diesel, aside from the burden of carrying on with the production in the wake of Paul Walker's death. Producer Neal H. Moritz also shot down reports of the filmmakers having issues with Vin Diesel, stating they "wouldn't be making the eighth film" with him if there was any trouble. Here's what a Universal spokesperson had to say about James Wan and Fast & Furious 8.

"The studio and filmmakers loved working with James on Furious 7, but he was never in the mix for an eighth film due to a scheduling conflict with The Conjuring 2. We are actively casting and searching for the right director for the next chapter of the franchise."

Vin Diesel's deal with Universal stipulates that the actor/producer must be consulted with about who will direct Fast & Furious 8, but he doesn't have the power to veto any of the studio's choices. Universal has reportedly put out "feelers" to experienced action directors like Jaume Collet-Serra, who was not available to come aboard, and newcomers as well. Other sources claim the studio "fears" that Vin Diesel will want to direct one of these movies himself. The actor did already write and direct the 18-minute short film Los Bandoleros, which set up his return in Fast & Furious, but other sources claim he doesn't want to "expose himself to such scrutiny" by directing a massive action project. Universal reportedly wants to make three more movies after Furious 7. What do you think about these new details? Who do you think should direct Fast & Furious 8?