Class reunions are a rite of passage for high school graduates, fictional or not.

The cast of "Saved by the Bell' – including Mario Lopez, Tiffani Thiessen, Mark-Paul Gosselaar and Elizabeth Berkley – celebrated 30 years of friendship over dinner at Petit Trois in Sherman Oaks, California, earlier this year, ahead of the NBC series' 30th anniversary on Aug. 20.

"Friends forever," Lopez, 45, wrote alongside a group shot of the former child stars posing with their significant others on Instagram.

In an additional video, Lopez said, "Fun dinner tonight with some old friends. … We ate an obscene amount of food. … Great group right here, now it’s time to play credit card roulette for the bill."

Related: Mark-Paul Gosselaar reflects on career, 'Saved by the Bell' romances and 'The Passage'

Although fans of the hit '90s show didn't get a chance to witness the friendly game of credit card roulette, Gosselaar may have shed a little light on who covered the check.

"Thanks for taking care of the bill!" he replied to Lopez.

Gosselaar shared the reunion picture on his Instagram, writing, "This is what 30+ years of friendship looks like."

Lopez, Thiessen, Gosselaar and Berkley catapulted to fame on "Saved By the Bell," which spanned five seasons from 1989-1993, as A.C. Slater, Kelly Kapowski, Zack Morris and Jessie Spano, respectively.

The cast also included Dustin Diamond (Samuel "Screech" Powers) and Lark Voorhies (Lisa Turtle), who were not present at the gathering.

Related: Mark-Paul Gosselaar says 'Saved By the Bell' cast earn no residuals because of 'bad deals'