Would you believe there’s someone who has appeared on more seasons of Saturday Night Live than Kenan Thompson? Thompson has been part of the cast for 22 seasons now, a record that no one else is even in shouting distance of. (Darrell Hammond is second with 14 seasons — Thompson has 50 percent more years under his belt.)

And yet, there’s a non-cast member who blows Thompson away, appearing on 29 of the show’s 50 seasons — including the current one. Starting with Season 15 (the 1989-1990 year), this performer has appeared in all but seven SNL seasons.

The answer? Lorne Michaels’ good pal, Alec Baldwin.

On the one hand, that fact isn’t so surprising. After all, Baldwin has topped Steve Martin as the comic actor who’s hosted the show the most times. But those 17 headlining gigs only get Baldwin a little more than halfway there. Baldwin has popped in without being on the bill during 12 other seasons,...