Late Show with David Letterman - Season 3 Episode 150

Frisco, Day 5: The Alcatraz mock-up in the backdrop is subject to a jailbreak; Dave hangs out with a local hippie, thus introducing the world (not to mention fleeting fame) to one Manny Papp; Dave loses a blue card, and then finds it inside a crab at Fisherman's Wharf; Manny meets his hero, John Popper of Blues Traveler.