'This Is Us' Star Milo Ventimiglia Reveals Whether Old Jack's Back in Season 3

Tuesday's season finale of This Is Us will feature Jack Pearson as an old man, even though he never lived to see his hair turn grey. Will we see him in that form again? Star Milo Ventimiglia played coy when asked if this was more than a one-time thing.

Previews for the finale show Jack as a 70-year-old man attending Kate Pearson's (Chrissy Metz) wedding. However, Jack was 53 when he died.

"You will know why I am in aged Jack makeup," Ventimiglia told Entertainment Tonight at SXSW in Austin, Texas. "I don't want to tease anything other than you've seen the photos. Just be excited and enjoy."

When asked if Jack will show up as an old man again, Ventimiglia sounded doubtful.

"I feel like that's maybe a one-time thing. It's only once in your life, like a particular blooming flower," the Emmy nominee said.

Although the makeup likely will not be used again, the This Is Us crew took their time to make sure Jack looked great as an old man. It took the makeup artists three hours to do it.

"It's a lot, but you can't help but feel like you're in your 70ish years when you're in it," he told ET. "We were in between scenes and I was talking to someone and how [I was] standing, I couldn't get out of 70-year-old Jack."

Mandy Moore was also at SXSW, and told ET she was "pleasantly surprised" about seeing Jack show up in the present scenes in the finale's script. Moore plays Jack's wife and the matriarch of the Pearson family, Rebecca Pearson.

"It sort of makes you wistful for what could have been," Moore said of Jack's appearance in the finale.

Ventimiglia will still appear in the third season of This Is Us, as the series continues to explore his character's past. The show is also going to jump into the future, as we have seen an older Randall and his daughter, Tess, as an adult.

"[Creator Dan] Fogelman's intention was always to jump into the future and that was something we all knew going in. When we saw them jump into adult Tess and older Randall, that was where he always wanted to go," Ventimiglia told ET. "I don't know if the show always lives there, but I think understanding that we do exist in the past, it makes sense that we'd exist in the future as well."

The last episode of This Is Us' second season, "The Wedding," airs on Tuesday at 9 p.m. ET on NBC. The show was already renewed for a third season.