VIDEO: Watch the Amazing Full House Reunion on Jimmy Fallon

Have mercy!

The Full House nostalgia train kept rolling on Late Night with Jimmy Fallon Wednesday, with Bob Saget, John Stamos and Dave Coulier reprising their roles as Danny Tanner, Uncle Jesse and Joey from the beloved sitcom.

Photos: Full House and other TV shows that should reunite

In the skit, the guys take it upon themselves (along with sappy string music) to comfort Jimmy Fallon, who's nervous about leaving Late Night to take over hosting duties at The Tonight Show. And even Mr. Woodchuck makes an appearance!

The trio also filmed a Full House-themed commercial that will air during the Super Bowl on Sunday. Check out their appearance on Late Night below: