Four years ago, Taron Egerton revealed on “Watch What Happens Live” that his celebrity crush was Rachel Weisz. But he probably never thought anyone would tell her. When we surprise them both with the clip during this conversation, Egerton turns bright red with embarrassment. Beyond that connection, both actors have stretched to new heights on streaming shows this TV season. Weisz portrays identical twin gynecologists Elliot and Beverly in the Amazon Prime Video drama “Dead Ringers,” based on the 1988 David Cronenberg film starring Jeremy Irons. And Egerton gets jacked as prisoner James Keene, a former college football star arrested on drug charges, in Apple TV+’s “Black Bird.”