Fans of 9-1-1 continue to grieve the on-screen death of Peter Krause’s cherished character, Bobby Nash. The impact of the fire captain’s pivotal exit extends beyond viewers, as the show’s cast and crew are also deeply affected by this significant plot twist.

In a conversation with Good Morning America on May 12, Oliver Stark, a star of 9-1-1, spoke about Krause’s emotional departure and disclosed how unexpectedly the news reached the ensemble.

“The rest of the cast and I got the news just about two weeks before the actual filming took place, so we didn’t have much time to say our goodbyes,” Stark shared, admitting that he was at a loss for words upon learning about the Season 8 developments. “When I received the call, I was honestly speechless. Tim Minear, our showrunner, even checked to make sure I was still there on the line by asking, ‘Are you still there?’ and I just said, ‘Yeah. I don’t know what to say.’”

Krause’s character died during 9-1-1: Contagion, a thrilling two-part Contagion-inspired event that saw Bobby and three members of the 118 trapped in a bio lab exposed to a deadly virus. After learning that Chimney (Kenneth Choi) contracted the virus and his organs were shutting down, Bobby sacrificed his own life to ensure his friend received the sole anti-viral. After revealing his own exposure and symptoms, Bobby said an emotional goodbye to his wife Athena (Angela Bassett) before succumbing to his rapidly onset illness.

“It was shocking, and stunning, and it’s sad,” Stark told GMA when reflecting on Bobby and Krause’s departure from 9-1-1. “We’ve had eight years of building a really close-knit family and we’ve lost our patriarchal figure.”

Though Stark’s character Buck lost his on-screen father figure, GMA reminded him that he still has a sister in 911 dispatcher Maddie, played by Jennifer Love Hewitt.

“We actually met here in New York some six or seven years ago now, and pretty much immediately she was making fun of me like my sister would,” Stark laughed, talking about his close-knit relationship with Hewitt. “The family bond was in-built and she’s so great and she’s so goofy. She doesn’t take herself at all seriously, so it’s really easy to have that sibling dynamic.”

While Stark couldn’t give away any specifics about 9-1-1‘s upcoming Season 8 finale, set to air on Thursday, May 15, the actor did share the story of how he considered becoming a real-life firefighter before landing this role. He also opened up about his long-running joke with the 9-1-1 props department and spoke on his passion for photography.

9-1-1 fans have likely seen Stark’s behind-the-scenes set photography shared on Instagram, but the actor revealed he has a grander plan for the photographs he’s been snapping on-set.

“We’ve been doing the show a long time, eight years now. I was looking for ways to feel creative again. I love taking photographs, and we do such specific things on this show that it felt nice to organize them,” Stark explained. “So yes, I’ve been creating this coffee table book that I’ll give to the cast and crew at the end of the season as a nice way too look back and go ‘We’ve had some really good times.’”

Before 9-1-1‘s cast, crew, and fans say goodbye to Season 8, there’s still one more episode left to air, so be sure to tune in to see how Minear wraps up the latest 18-episode run.

9-1-1‘s Season 8 finale premieres Thursday, May 15 at 8:00 p.m. on ABC with next-day streaming on Hulu.