It’s a reunion 35 years in the making, thanks to mayonnaise. More than three decades after the romantic comedy “When Harry Met Sally” first hit theaters, Billy Crystal and Meg Ryan are finally back together.

It's time to return to Katz's Deli with the stars of "When Harry Met Sally" – this time though, it's for a Super Bowl ad

Meg Ryan and Billy Crystal recreated a classic scene from "When Harry Met Sally" for a new Super Bowl ad, with a special appearance by Sydney Sweeney.

The two actors revisit an iconic scene from their legendary romantic comedy in the commercial, a nostalgia play titled “When Sally Met Hellmann’s” (watch below). Ryan and Crystal play friends whose connection turns romantic in the 1989 movie written by Nora Ephron and directed by Rob Reiner.

Super Bowl 59 kicks off Feb. 9, but commercials featuring celebrities have already started rolling out in snippets. Brands pay big bucks to get their clips, which often have some of the hottest Hollywood talent available star in 30 seconds to a minute’s worth of a commercial.

Super Bowl LIX is already proving to offer serious star power, with ad spots led by Chris Pratt, Eugene Levy, Michelle Rodriguez and even a When Harry Met Sally reunion with Meg Ryan and Billy Crystal.

Billy Crystal and Meg Ryan have reunited for the 60-second ad 'When Sally Met Hellmann’s,' as they recreate the famous Katz Deli scene from 'When Harry Met Sally.'

It was so much fun,” Crystal told The Post of reuniting with Ryan more than three decades after their iconic 1989 rom-com.

We finally know why Billy Crystal and Meg Ryan are reuniting. The two reunite at the deli from "When Harry Met Sally" for a new ad for mayonnaise. Gino Salomone joins FOX6 WakeUp with the Hollywood headlines.

Meg Ryan and Billy Crystal recreate the "I'll have what she's having scene" from their famous film in new Super Bowl ad.

Billy Crystal and Meg Ryan are back together as Harry and Sally in a new commercial for Hellmann's mayonnaise set to air during the upcoming Super Bowl. Its opening line: "I can’t believe they let us back into this place," Crystal’s Harry tells Ryan’s Sally over lunch at Katz’s Deli on Manhattan's Lower East Side.