The actress shot the web drama series while shooting Season 6 of the HBO vampire series
"He and my husband [Stephen Moyer] have worked together a bunch of times and known each other for many, many years," Paquin told TheWrap.
"Our families are all really close," she continued. "He and I had been talking about wanting to work together at some point. He wrote the first episode of what is now 'Susanna' and showed it to me, and I thought it was wonderful."
"Black Swan" producer Avnet and "In Treatment" director Rodrigo Garcia started web network WIGS and recruited well known directors and stars for its projects.
"What's incredibly impressive is that it feels like you're shooting a film, which is actually pretty much the same experience I've had working on TV for HBO," Paquin said of shooting "Susanna."
"So, I'm not even sure I've experienced real TV in the traditional sense. The people that [Avnet] works with are all filmmakers and in the world of film. Even though they're tiny segments, the attention to detail and the production value and all the effort that's put into it feels like you're shooting a film."
In order to take part in "Susanna" — in which Paquin plays new mother Katie, who suffers from postpartum depression – the actress had to shoot her scenes on the weekends while "True Blood" was in production.
"It was the only time we could fit in," she explained. "There's something palate-cleansing about going and doing something else entirely over the weekend, so that when you come to the other job on Monday you've been in someone else's head, in someone else's world. And there's something actually kind of interesting and great about that, so that you are not dragging last week in. It's all fresh again."
Paquin co-starred with Maggie Grace, who played her sister Susanna. An investment banker on the rise, Susanna has to take care of her sister and her child while trying to keep her career from derailing.
See photos: 'True Blood' Releases 22 Shots From Season 6
"It was pretty intense and upsetting, but, also, I like that," Paquin said. "I like going to work and being challenged."
Watch the first episode of "Susanna" below: