Treat Williams' Wife Pam Says He Was 'Truly in His Element' Filming “Feud: Capote vs. The Swans” (Exclusive)

Pam Williams tells PEOPLE how her late husband, who died in June, "couldn’t have been happier" to be working on what became his final project

When Treat Williams died in June following a motorcycle accident, he left behind a treasure trove of TV and film performances. But his final project airing in late January could very well be one of the late actor’s personal favorites.

In an exclusive interview with PEOPLE, the late actor’s wife Pam Williams shares how Treat “couldn’t have been happier” working on FX’s Feud: Capote vs. The Swans, which premieres on Jan. 31.

Created by Ryan Murphy and directed by Gus Van Sant, the limited series stars Naomi Watts, Diane Lane, Chloë Sevigny, Calista Flockhart, Demi Moore and Molly Ringwald.

Related: Feud Trailer Shows Demi Moore, Calista Flockhart and More as 'Swans' Out to 'Destroy' Their Gossipy Guy Pal

Pam says working on the star-studded production was a thrill for Treat, who played CBS executive Bill Paley in the new series.

“He was truly in his element working with the best of the best in every department on this project and couldn’t have been happier,” says Pam, who joined Treat in New York City for much of filming.

Related: Treat Williams' Wife and Kids Remember the Actor 7 Months After His Death: 'He Was and Is Our Hero' (Exclusive)

Immediately following Treat’s tragic death, Pam says the show’s production crew reached out with their “condolences and support,” emphasizing “how proud we will be of his performance.”

With Feud: Capote vs. The Swans debuting in just a few weeks, Pam admits she and her children —  Gill, 31, and Ellie, 25 — whom she shared with Williams, haven’t mentally prepared themselves to see Treat onscreen one last time.

“I haven’t given it much thought, but it’s horrible thought to think I’ll be watching his last project — not a comfortable place to be or think about — but of course we’ll be there to support him as always,” she says, adding that while it’s been seven months since Treat’s death, “It still feels like yesterday on most levels.”

Related: Treat Williams' Wife Pam and Children Remember His 'Beautiful Legacy' as He Would Have Turned 72 (Exclusive)

Treat, whose decades-long career included roles in Hair, Everwood and Chesapeake Shores, died on June 12 at age 71 following a motorcycle accident in Dorset, Vermont. (A trial date for the other driver in the accident, Ryan Koss, who pleaded not guilty, has not been set.)

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer.

While the Golden Globe and Emmy-nominated actor's death shocked fans and former costars, it also completely blindsided Pam, Gill and Ellie who continue to process his loss.

"I think because of the suddenness of it, there was absolutely no preparation, so I'm still grappling with the fact that it happened and that he's really gone," Pam says. "It just feels like such a hole in our family and the fabric of the world. The whole atmosphere feels different."

Related: Treat Williams' Life in Photos

As the months pass, Treat's family believe one of the easiest ways to remember him is by rewatching his work.

"He's left behind this beautiful legacy. That's something you're very lucky to have if your parent is an artist, especially when they're as prolific as him, because you get to, in many ways, still be with them through that," Gill explains. "Even if it's a character, his heart and his soul are actually present in all of his work."

For more on Treat Williams and his family, pick up the latest issue of PEOPLE, on newsstands Friday, or subscribe here. 

Feud: Capote vs The Swans' first two episodes air on Wednesday, Jan. 31 at 10 p.m. ET on FX and will be available to stream next day on Hulu.

For more People news, make sure to sign up for our newsletter!

Read the original article on People.