Alec Baldwin — who’ll host “Saturday Night Live” for a record 17th time this weekend — waxes nostalgic in a new black-and-white trailer released Wednesday by NBC.

“This was my home,” Baldwin says as he walks the halls of Studio 8H. “This was my heartbeat. It feels like so many lifetimes ago.”

As he strolls, we see bits of footage from his other times as host. “I thought I had said goodbye, but the pull of fate is undeniable. So I must return, I must find the strength to . . .”

Suddenly, “SNL” regular Vanessa Bayer interrupts, reminding the Massapequa-raised actor that he hasn’t really been gone that long from the show — especially since he started portraying Donald Trump last year.

“You were just here yesterday . . . It’s not a big deal,” she says.

“Oh, it’s a big deal,” he replies.