Last night marked the sixth time Scarlett Johansson hosted Saturday Night Live, so there was some expectation of switching things up and going even bigger to mark this special occasion. Johansson's opening monologue set the tone for the night, running five minutes long and including jokes related to Avengers: Infinity War baddie Thanos, her fiancé and "Weekend Update" anchor Colin Jost, and the forthcoming NBC streaming service Peacock. [caption id="attachment_859795" align="alignright" width="360"] Image via Saturday Night Live/NBC[/caption] Much of Johansson's opening monologue is centered on SNL cast members suddenly getting snapped out of …