When Samuel L. Jackson stopped by Late Night with Jimmy Fallon on October 11 to promote his Broadway play The Mountaintop, the Oscar nominee decided to get with the times and activate his Twitter account. Not surprisingly, Jackson dropped a few F bombs in his first tweet from Fallon's couch. After putting his iPad down, Jackson discussed the challenges of returning to the stage for the first time in 15 years and how he went about capturing the distinctive voice of Dr. Martin Luther King Jr. He also debuted the preview for his upcoming superhero movie The Avengers, then hopped off the couch to play a game of home run derby, joining Fallon to bat giant foam balls into the audience. Take a look at all the fun below!