Las Vegas is a city in Nevada internationally renowned for gambling, shopping, fine dining, and nightlife.
On one Christmas Eve, Peter Venkman was planning to go to Las Vegas and partake in an "All You Can Eat" festive buffet at Caesar's Palace. Once Ray Stantz informed him that Woodrow Wainwright Fraser III wanted to hire the Ghostbusters for a job, Peter canceled his travel plans.  
A few years later, in the latter half of the summer cross country trip, Peter separated from the other Ghostbusters. He drove Ecto-1a and departed the 285 in New Mexico and took the I-40 to Las Vegas for a couple days of relaxation. About a year later, Winston Zeddemore and Tiyah Clarke took a free vacation to The Olive in Las Vegas in exchange for Winston discreetly trapping a Vegas Ghost pestering patrons.
During an expansion plan, the Olive inadvertently triggered the manifestation of the ghost of stage magician Ethan Kaine by closing and demolishing his old venue, the Golden Spade.  Kaine tapped into the power stored in a River of Slime under Las Vegas and transformed buildings along the strip into skewed versions of the past. To make matters worse, Kaine also acted as a beacon and attracted a legion of ghosts to the city. Initially, the remaining casinos still standing played along with the paranormal activity and took bets on what the ghost would attack next. Special Agent Melanie Ortiz was brought in by the FBI to intervene. However, the skewed buildings began to shift to more nightmarish emanations. She contracted Ray Stantz from the New York branch and Ron Alexander, Lou Kamaka, and Dani Shpak from the Chicago branch. Ron, Lou, and Dani lured the legion of ghosts away while Ray attempted to pin down Kaine. Ray and Melanie followed his hunch and explored Las Vegas' network of tunnels where they found a River of Slime. Evidently, the Psychomagnotheric Slime stored the emotional energy of gamblers over the decades. Ray wired a canister of positively charged Psychomagnotheric Slime to a Proton Grenade and tossed it into the river. Kaine's connection to the river was destroyed but the resulting explosion also sent slime up into the fountains of the RKO Casino. The affected buildings suddenly began to return to normal except the Olive.  Lou and Dani trapped Kaine. The untrapped ghosts faded away. Ron claimed a ghost with "crazy hair" who wore a black and white suit promised to return in the near future to "shake things up." The RKO Casino's fountains were contaminated, fully drained, and cleaned. The casino demanded a $470,000 reimbursement from the Ghostbusters and the FBI.  An early-warning P.K.E. monitor was installed at the local FBI field office.
- In the July 6, 1983 draft of Ghostbusters, Egon Spengler and Janine Melnitz got married in Las Vegas with Louis Tully as their witness. 
- Past, Present, and Future
- Mentioned by Ray on page 3 and by Peter on page 4
- Ongoing Series
- Egon Spengler (2011). IDW Comics- "Ghostbusters Volume 1 Issue #3" (2011) (Comic p.12). Egon Spengler says: "Not the experimental pack our former associate used, it shorted out in Vegas."
- Ray Stantz (2009). IDW Comics- "Ghostbusters: Past, Present, and Future" (2009) (Comic p.3). Ray Stantz says: "You were heading for Vegas this morning until I told you a millionaire wanted to hire us."
- Peter Venkman (2009). IDW Comics- "Ghostbusters: Past, Present, and Future" (2009) (Comic p.4). Peter Venkman says: "It's not like Caesar's Palace was having an "All You Can Eat" festive buffet incorporating erotic dance or anything."
- Spectral Incident Report (2016). IDW Comics- "Ghostbusters International #7" (2016) (Comic p.23). Spectral Incident Report reads: "The closure and demolition of a small, run-down casino - The Golden Spade - to make way for an expansion of the much larger Olive Hotel and Casino was the trigger for the manifestation of a spectral magician, whose set to transforming the buildings along the strip."
- Spectral Incident Report (2016). IDW Comics- "Ghostbusters International #7" (2016) (Comic p.23). Spectral Incident Report reads: "The buildings on the strip started to revert to normal, with the exception of the Olive, which remained transformed until Kaine's ghost was trapped by Kamaka and Shpak."
- Spectral Incident Report (2016). IDW Comics- "Ghostbusters International #7" (2016) (Comic p.23). Spectral Incident Report reads: "The fountains of the RKO Casino (a closed system) were contaminated and required a full draining, cleaning, and refilling, which cost $470,000. The casino is demanding reimbursement from the Bureau and Ghostbusters for this."
- Shay, Don (November 1985). "Making Ghostbusters", p. 203. New York Zoetrope, New York, NY USA, ISBN 0590336843.
- Peter Venkman (1999). Ghostbusters II (1989) (DVD ts. 01:28:37-01:28:42). Columbia Pictures. Peter says: "Keep kicking, Libby! You make this work, we'll pop for a weekend in Vegas with the Jolly Green Giant!"
- Peter Venkman (2014). IDW Comics- "Ghostbusters Volume 2 Issue #13" (2014) (Comic p.10). Peter says: "Hey, if they wanted class, we should've done this in Vegas."
- Peter Venkman (2016). IDW Comics- "Ghostbusters International #4" (2016) (Comic p.6). Peter Venkman says: "We're like a chapel in Vegas, Winston. Bad ideas are kind of our bread and butter."