You should back up such openers by a good story, f.e.: "yeah, because my friend, he was blablabla ...". Make up such stories, lie if necesairy

. You can keep going on this and the conversation can roll in something else.
A common transition is "how do you know each other?", to which they will look at each other if they know them for a long time to which you can say "you I bet that you 2 are very good friends" and they might be like "omg how do you know that???"
Or, just very casualy and spontaneously, ask them "hey did you also go to the party? how was it?" and continue from there.