Mark Ruffalo in the HBO series "Task."
FBI agent Tom (Mark Ruffalo) with fellow agent Anthony (Fabien Frankel) in "Task."
Mark Ruffalo as Tom, Alison Oliver as Lizzie, Thuso Mbedu as Aleah and Fabien Frankel as Anthony in "Task."
Brad Ingelsby talks with Mark Ruffalo on the set of HBO's "Task."

Mark Ruffalo can explain why he looks so emotionally unmoored as Philadelphia FBI agent Tom Brandis in HBO’s drama "Task" (premiering Sept. 7, Sundays at 9 ET/PT).

The Marvel Cinematic Universe Hulk star, 57, had entered a turbulent Pennsylvania world created by Berwyn-born Brad Ingelsby: The gritty series is set in the same Delaware County — known locally as Delco — suburbs as Ingelsby's 2021 Emmy-winning series "Mare of Easttown."

“I’ve been in the ICU,” Ruffalo says, before quickly clarifying. “That’s the Brad Ingelsby Cinematic Universe.”

In "Mare," British Oscar-winner Kate Winslet eschewed makeup and unceremoniously ate a Philly cheesesteak as a world-weary police detective and former high school basketball star.

Ruffalo's priest-turned-FBI-agent grieves the murder of his wife, while heading a task force seeking Robbie (Tom Pelphrey), the unlikely perpetrator of violent drug-money robberies.

"There's so much working around this character from the moment we find him," says Ruffalo. "It was like, 'This is going to be intense.' And it was intense."

Writer and executive producer Ingelsby drew inspiration for the complex character from an uncle, a former Augustinian priest who left the order to marry. He was further influenced after learning that the FBI often calls on priests, rabbis and other clergy members to counsel victims at mass-casualty events.

He fleshed out the complex FBI character, who never loses his compassion despite his grueling job and his devastating family drama.

Ingelsby says Ruffalo was an obvious choice. "There's nothing special about Tom as an FBI agent; he isn't the first in the guy in the door," he says. "Tom's superpower is his empathy. Many of the great qualities Tom has, Mark also has a person. So we tapped into that."

How Mark Ruffalo dealt with the 'Delco' accent in 'Task'

A defining feature of Ingelsby’s world is the "Delco" accent — distinctive, specific, and notoriously difficult to reproduce. Winslet successfully shed her British accent, earning acclaim and a second best-actress Emmy.

Ruffalo, born in Kenosha, Wisconsin, says he worked extensively with dialect coach Susanne Sulby, "who was so patient with me. I kept wanting to slip into Wisconsin or New York. The accent is specific and so weird and so idiosyncratic," says Ruffalo. "It's like the South meets Baltimore, with a little Italian and Irish accents sprinkled in."

Ruffalo was impressed with how naturally British actors like Emilia Jones, who stars as Maeve, Robbie's niece, mastered the tricky American accent. His international castmates playing young FBI agents — Fabien Frankel (British), Alison Oliver (Irish), and Thuso Mbedu (South African) — also crushed it, which Ruffalo found "just amazing."

How Ruffalo put on the weight to play 'Task' character

In addition to the vocal difficulty, there were other challenges. Ruffalo wanted to show the physical effects of heavy-drinking Brandis' heartbreak over his wife's death and the impact on his family. This emotional storyline is explored in "Task" as much as the FBI's quest to solve the robberies.

"The series is really cops and robbers, with 100% driving pulse and twists," says Ruffalo. "But Brad not only masters the real crime but takes deep dives into the complexities of people and their lives."

Ingelsby says it was Ruffalo's idea to grow the unkempt beard, and to show that the troubled character has put on significant weight. "We wanted to lean into the tragedy aftermath," he says. "The anchor of the family is gone. As parent and in terms of what he's eating and drinking, Tom is adrift."

Ruffalo opted for padding, or "enlargement augmentation" to add 30 or 40 pounds to his frame. The costume designers initially pulled out a prosthetic baby bump. "I was like, 'Let's just put that on,'" says Ruffalo. "My assistant was like, 'Hey, Mark, nothing for nothing. But no one wants to see you as a fat FBI agent.' I was like, 'Thank you.'"

Still, Ruffalo continued with the large prosthetic, which was an initial surprise to the producers and higher-ups. "There was some grumbling," he says. "And then they were like, 'OK, we see what he's doing.' "

Ingelsby recalls saying, "Wow that's a big pad. Maybe take like half of that. We ended up shaving it down a bit. We found the middle ground."

Not having to put on weight for the "Task" role is going to be helpful should Ruffalo return, as rumored, to the MCU and his Hulk role in upcoming "Spider-Man 4." The body-hugging motion-capture suit used to create the Hulk on screen is notoriously unforgiving

"We don't know if that role is for certain; let's knock on wood that it transpires. That's my bread and butter," says Ruffalo. "But you have to be in great shape for that role. There's no hiding anything in that suit."

This article originally appeared on USA TODAY: For HBO's 'Task,' how Mark Ruffalo added weight and mastered a tricky accent

Reporting by Bryan Alexander, USA TODAY / USA TODAY

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