Lenny is particularly short and old for a ghoul, having turned into one at a mature age. Before the Great War transformed him, he was an accomplished medical doctor, with a practice in Bakersfield. When the War came, he and his father, William, sought refuge in Vault 12 beneath the city. The Vault was designed to malfunction and the entire Vault Dweller population was turned into ghouls. Lenny used his talents to help others in the Necropolis, flying under Set's radar and avoiding violence. This helped him survive the super mutant attack intact.
Around 2161, the stuttering ghoul saw a man running through the city: the Vault Dweller. Lenny instantly recognized him as an outsider and when he passed by, Lenny almost reached out to stop him to ask if he could join his quest. But he did not; he lacked the courage to do so. Lenny never forgave himself for this, especially when he learned that the Vault Dweller wiped out the Master's laboratories, destroying the Unity.
Before he heard that news, Lenny and his father just barely survived the super mutant retaliation that killed most ghouls in Necropolis. He migrated north, until he finally arrived in Gecko, where he settled as a doctor and aide to Harold, helping manage the town's affairs and healing those who were hurt. The neighboring Vault City quickly turned out to be a painful reminder of his fate as a ghoul. If given the chance, he would trade his extreme lifespan in for a life as a regular human, using Vault City's technology to heal himself; but Vault City-grade bigotry would never allow this.
Lenny had resigned himself to a life of a glorified bureaucrat until the Chosen One arrived in the city and he unexpectedly received a second shot at a grand quest to save the wastes.
When the Chosen One comes to Gecko, he can recruit Lenny to his party. He is very durable as a party member, is capable (growing to be skilled) with pistols and SMGs, and is human-shaped enough to wear armor, in addition to being a skilled doctor. He has only 4 Strength, enough for a H&K P90c. Lenny remains at 7 AP through all his levels. If his strength is increased by being equipped with power armor, enough to use a .223 pistol or even Gauss pistol, Lenny can make an effective supporting member, especially if his Doctor skill is at a higher level than the Chosen's own. Care must be taken however, as Lenny usually enters in the middle of the line of sight in a fight to cure the Chosen One, even if told to wait at a location.
Lenny provides affordable healing services at Gecko. If he is recruited and dropped off, he will no longer provide these services.
Lenny can trigger many restrictions when dealing with certain characters: many people will refuse to do business with Chosen One if Lenny (or Marcus) is in their party, such as Louise in Redding's Malamute saloon.
Cassidy will constantly complain about how bad Lenny smells and recommend remedies for his stink.
If the Chosen One joins the Slaver's Guild in the Den while Lenny is in company, Lenny will express disgust at the Chosen One, saying he is a "disgrace to the Vault Dweller's memory," and disband. He will also disband if the Chosen's Charisma drops below 5 while Lenny is recruited, or he is given too many orders to move or change position, Lenny will complain about the Chosen One being "cantankerous and ornery". The former situation is rarer, however.
Lenny was designed by Fallout 2 lead designer Matt Norton. The player was supposed to be able to turn Lenny into a glowing ghoul with copious amounts of Gamma Gulp beer and Roentgen rum, but this functionality was scrapped, likely as a function of the fact that doing so would prevent Lenny from using any weapons except for unarmed ones.
Chris Avellone in Extrasode Episode 61 criticized the design of Lenny, describing him as a character whose function in the game is to be shot at.
↑Lenny's character description: "You see an especially short, older ghoul." "You see Lenny, Harold’s assistant." "You see a short, older ghoul. He appears to be preoccupied." (GCLENNY.MSG)
↑ 3.03.1The Chosen One: "What do you do here?" Lenny: "W’well, I h’help H’harold mostly. Wh’when people get hurt, I h’help them out." The Chosen One: "What else did you say you did here?" Lenny: "I h’help H’harold administer the town. Th’there’s always more p’paperwork to do." The Chosen One: "You can heal people?" Lenny: "Well, b’before the W’war I w’was a doctor." The Chosen One: "Before the war? But that must have been almost 160 years ago." Lenny: "That's t’true. B’but the radiation seems to have g’given us g’ghouls a longer life-span. ‘Course, it took almost eveything else away." (GCLENNY.MSG)
↑Lenny: "I hear that you’re the Descendant of the Vault Dweller. You know, I met the Vault Dweller once." The Chosen One: "You met my ancestor?" Lenny: "W’well. I didn’t actually m’meet the V’vault Dweller. But I saw them. Once. " The Chosen One: "You saw the Vault Dweller? Where?" Lenny: "I’it w’was a long time ago. In a place called N’necropolis. A lot of us g’ghouls lived there. One, day I saw someone running through the city." The Chosen One: "Running?" Lenny: "Yes, running. You see, we ghouls c’can’t run too much anymore. So, I knew it was an outsider when I saw them. They ran by so close I could have touched them. I wish that I had joined the Vault Dweller.…" The Chosen One: "You wanted to join my grandsire?" Lenny: "Yes. I h’had the chance of a lifetime and I blew it." The Chosen One: "What do you mean?" Lenny: "L'later, I h’heard that the Vault Dweller had fixed our water system. The V’vault Dweller saved us -- all of us. Do you understand? It didn’t matter that we were ghouls. For once it didn’t matter. We w’were people again. W’worth saving." The Chosen One: "My ancestor was the founder of our tribe. That memory is revered amongst my people." Lenny: "Later, I heard that the Vault Dweller destroyed the source of the m’mutant army. The Vault D’dweller saved all of us. Human and ghoul alike… I could have been a part of that, but I lacked the c’courage. I’ve never forgiven m’myself." (GCLENNY.MSG)
↑The Chosen One: "Took things away?" Lenny: "W’well, y’yes. We look l’like f’friggin’ f’freaks. We d’don’t have any skin, for Chrisakes." The Chosen One: "Well, I guess you have seen better days." Lenny: "Y’you c’could say that. I’d trade in all those years to b’be a n’normal person again." The Chosen One: "Well, not much hope of that, I suppose." Lenny: "If those f’fools in Vault City w’would share their medical technology, I’m sure we could c’cleanse the excess r’radiation and heal ourselves." The Chosen One: "They won’t help you?" Lenny: "Y’you’ve been to Vault City? Then you t’tell me wh’what you think the chances of g'getting h’help from those bigots is. M’might as well watch a p’paper dog chase an asbestos c’cat through hell." The Chosen One: "I’m sorry to hear that, but I think you’re right. Let me ask you about something else." (GCLENNY.MSG)
↑Lenny: "Later, I heard that the Vault Dweller destroyed the source of the m’mutant army. The Vault D’dweller saved all of us. Human and ghoul alike… I could have been a part of that, but I lacked the c’courage. I’ve never forgiven m’myself." The Chosen One: "I am following in my ancestor’s footsteps. Would you like another chance? Will you join me?" "I'm h'happier than a bull b'brahmin in a pasture-full o' cows! I'd b'be honored to j'join you. I m'may be old and I cain't m'move t'too darn fast, leastwasy not for too long, b'but I kin sure p'patch you up when y'you need it." (GCLENNY.MSG)
↑John Cassidy: "Ghoul-boy, you better keep your damn distance. Shoooo-weee, do you stink." (VCCasidy.msg)
↑John Cassidy: "Dammit, Lenny, you need a bath. Or some disinfectant." (VCCasidy.msg)