Faking It Onstage

Let's start with the fake orgasm. The scene everyone remembers from Rob Reiner's iconic 1989 romantic comedy When Harry Met Sally is the one in which Meg Ryan's mischievous Sally shows Billy Crystal's bemused Harry just how women fake it — in a restaurant (actually Katz's Deli in New York City, where the relevant table now bears a plaque boasting of its close encounter with the ecstatic Ryan).

So a major point of interest in the movie's starry stage adaptation, which opened last week in London's West End, is: How does Alyson Hannigan's Sally measure up? Answer: She...