Jimmy Fallon Gives Surprise Commencement Speech at Marjory Stoneman Douglas High School Graduation

He lightened the mood.

Late night TV host Jimmy Fallon surprised students at Marjory Stoneman Douglas High School Sunday as he took the stage during the graduation ceremony.

"You are not just the future ― you are the present," Fallon said to the 748 seniors during his commencement speech to the class of 2018. "Keep changing."

Fallon also thanked the students for their courage and his bravery and recalled times he spent with the survivors of the Feb. 14 mass shooting at the March For Our Lives gun control rally in Washington DC., in March.

Fallon also joked during his speech.

"You should feel incredibly proud of yourselves. That doesn't mean you should rest on your laurels — or your yannys,” Fallon said.

Seventeen students and faculty were killed at the Parkland, Fla., school when a gunman opened fire in its hallways.

Four students — Nicholas Dworet, Joaquin Oliver, Meadow Pollack and Carmen Schentrup — were honored with posthumous high school diplomas. 

Their degrees were accepted by family members.

Melody Herzfeld, a drama teacher at the school, said Fallon’s speech gave everyone a chance to laugh again.

"It was almost like giving permission," Herzfeld said. "It gave us a little bit of hope. It took our minds off of things for a little while. He was so respectful."