DaveWatch: Countdown to Letterman's Last 'Late Show,' Day 18

Scarlett Johansson, John Mellencamp and Todd Rundgren pay tribute to the man — but only one got a brain freeze

Scarlett Johansson on 'Late Show with David Letterman' on April 27th, 2015. Credit: effrey R. Staab/CBS/Getty

Late Show was all over the place on Monday night, a strange-but-watchable mixture of awkwardness, coolness, heartfelt emotion and surreal humor, conducted with varying degrees of interest by the man behind the desk. Call it the best — and worst — of David Letterman in a 60-minute nutshell.

Just about every episode during Dave's final month has included some sort of flashback to an earlier period of his show, and last night's came in the form of a "Best of Top 10 List Moments" package, which compiled highlights from ten celebrity Top 10s (including ones featuring Presidents Barack Obama and George W. Bush) — and which was worth watching just to hear the late Barry White say "Gubernatorial" again in his best bedroom growl.

Todd Rundgren provided a flashback of a different sort, leading the Late Show band through a series of his greatest hits (including "I Saw the Light," "We Gotta Get You a Woman" and "Can We Still Be Friends") that sounded great in the brief pre- and post-commercial break snippets we could hear, and which Dave seemed to enjoy immensely. Rundgren also played a willing comic foil during an endearingly silly segment in which Dave surprised the studio audience with free shakes from Steak 'n Shake, while "Free Shakes" flashed repeatedly on the screen; attempting to battle Dave brain freeze for brain freeze, the singer-songwriter attempted to chug his own shake in a single gulp, with predictably messy results.

After that heaping helping of goofiness, Scarlett Johansson's guest appearance felt incredibly stilted. The actress was obviously stoked to make one last appearance on the show (she'd made her Letterman debut in 1998 at the age of 13), but Dave seemed uncomfortable and unfocused in her presence. As he did last week with Robert Downey Jr., Dave pranked Johansson with a "clip" from The Avengers: Age of Ultron that turned out to be something else entirely — in this case, old black-and-white footage of a woman being harassed by a robotic lawnmower — but nothing else from their exchange was remotely interesting or memorable. (Put it this way: Dave certainly didn't become a late-night legend on the strength of half-assed questions like, "What are some of your favorite films that you've done?")

By contrast, John Mellencamp's guest appearance seemed to bring out an entirely different Dave. From the moment the pompadoured singer-songwriter walked out onstage, lit cigarette defiantly in hand, the Late Show host seemed completely at ease; the two grouchy "fellow Hoosiers" bantered about heart attacks and complained about Rundgren, Warren Zevon and Paul Shaffer not being inducted into the Rock and Roll Hall of Fame, all of which felt appealingly real compared to the vapid showbiz chat of Johansson's segment. Mellencamp's acoustic rendition of "Longest Days" — a stark meditation on mortality from 2008's Life, Death, Love and Freedom — acted as an additional palate cleanser, ending the show on a somber-but-honest note. Memo to Dave: If you get bored in your retirement, please consider putting a web series together that consists entirely of you and Mellencamp bickering with each other on a porch somewhere. We would totally watch that.