It’s Friday again. Let’s start with the arts.

If you like documentaries, you might know about the new Apple TV+ two-parter on Steve Martin, who launched from Saturday Night Live silliness into comedy albums and more than 40 films. Newer fans know him from Hulu’s acclaimed “Only Murders in the Building,” with Selena Gomez and Martin Short, an old friend he seems to keep as close as his beloved banjo.

Mr. Martin’s early career included the vicissitudes that come with finding fame. He doubted his own talent, he notes in the new show. What this energetic introvert knew he had, he says: a deep love of show business. Love is what documentaries showcase best.

Peter Rainer, a reviewer with some great career stories of his own, offers his take today on this “wildly versatile” comic artist and this story of self-reinvention.