Both Famke Janssen and Carolyn McCormick made guest appearances on Star Trek: The Next Generation (1987).
Famke Janssen and Edi Gathegi both played characters in Marvel's X-Men movies. Janssen played Jean Grey/Phoenix in X-Men (2000), X2 (2003), X-Men: The Last Stand (2006) and X-Men: Days of Future Past (2014) while Gathegi played Darwin in X-Men: First Class (2011).
With 4.76 million viewers, this was the most watched episode in the series.