JImmy Jam, Terry Lewis surprises Janet Jackson on stage in Inglewood, CA

Jimmy Jam (L), Terry Lewis surprise Janet Jackson on stage in Inglewood, CA (Oct. 16, 2015)

*A seemingly unscripted moment happened at the end of Janet Jackson’s celeb-packed, sold out concert at the Forum in Inglewood, Calif., on Oct. 16.

At the show – attended by the likes of Beyonce, Queen Latifah and Channing Tatum — Jackson thanked the audience for helping make her new album, “Unbreakable,” No. 1. The set debuted atop the Billboard 200 chart last week, giving the singer her seventh chart-topper, and making her only the third act with No. 1s in each of the past four decades.

“I want to thank you for making the ‘Unbreakable’ album No. 1,” Jackson told the audience. (Watch below.) She went on to thank her fans for their continued support, specifically noting how her “family has been in the entertainment business for 50 years.”

Then, she turned around. Her mouth flew open when she saw that her longtime producers, Jimmy Jam and Terry Lewis, had joined her on stage. (Jam and Lewis co-produced and co-wrote “Unbreakable” with Jackson, along with the bulk of her earlier catalog.) Jam embraced Jackson as a huge framed blowup of the “Unbreakable” album cover was rolled out on to the stage behind them.

“Oh my gosh, Terry!” Jackson exclaimed when she saw Lewis toting out a huge bouquet of white flowers. “What are you guys doing?” Jackson said, giggling. “Jimmy?”

Jam grabbed the mic and said, “So if you ever wanted to know what Janet Jackson looks like when she’s totally surprised, this is it, L.A. This is it. So, I just want to say real quick, first of all, I want to congratulate each and every one in this arena right now, because a No. 1 does not happen without all of you.”

Jackson nodded in agreement, looked out at the audience, and then pointed to the sky.

Jam continued, “But tonight is a very special night because it was around 30 years ago — if you can believe that — that we first got together in a little town called Minneapolis, Minnesota. And we had the first chance to work with Janet.”

Jackson interjected, “But we knew each other before then. We first met when I was 14.” Jam agreed, “Yeah, that’s true!”

“So, we’re not only celebrating the history,” Jam went on, “but the best part about it is we’re celebrating the right now, the right here tonight. So listen, we just wanted to celebrate with everybody here in L.A. tonight. It’s very special, because, trust me — she says it in the song — you don’t know what you got ‘til it’s gone. We waited seven years for a new project, and guess what? She’s back! We love you, Janet.”

Jam and Lewis hugged Jackson once more, and then bounced – leaving her to finish her final song of the night: “Unbreakable’s” title track.

Watch below: