Vegas Vacation is a 1997 comedy film

Comedy film

Comedy film is a genre of film in which the main emphasis is on humour. They are designed to elicit laughter from the audience. Comedies are mostly light-hearted dramas and are made to amuse and entertain the audiences...

. It is the fourth film in the original Vacation film series centering around the fictitious Griswold family, following Vacation

National Lampoon's Vacation

Vacation, sometimes referred as National Lampoon's Vacation, is a 1983 comedy film directed by Harold Ramis and starring Chevy Chase, Beverly D'Angelo, Randy Quaid, Dana Barron and Anthony Michael Hall...

, European Vacation

National Lampoon's European Vacation

European Vacation is a 1985 comedy film. The second film in National Lampoon's Vacation film series, it was directed by Amy Heckerling and stars Chevy Chase and Beverly D'Angelo. Dana Hill and Jason Lively replace Dana Barron and Anthony Michael Hall as Griswold children Audrey and Rusty...

, and Christmas Vacation

National Lampoon's Christmas Vacation

Christmas Vacation is a 1989 Christmas comedy film directed by Jeremiah S. Chechik. It is the third installment in National Lampoon's Vacation film series, and was written by John Hughes, based on his short story in National Lampoon Magazine, Christmas ‘59...

. Chevy Chase

Chevy Chase

Cornelius Crane "Chevy" Chase is an American comedian, writer, and television and film actor, born into a prominent entertainment industry family. Chase worked a plethora of odd jobs before moving into comedy acting with National Lampoon...

 reprises his starring role as Clark W. Griswold, the patriarch of the family. The film opened at #4 at the box office and grossed over $36.4 million domestically. This is the only theatrical Vacation film not to have the National Lampoon label.
At work, Clark Griswold (Chevy Chase

Chevy Chase

Cornelius Crane "Chevy" Chase is an American comedian, writer, and television and film actor, born into a prominent entertainment industry family. Chase worked a plethora of odd jobs before moving into comedy acting with National Lampoon...

) has invented a long life food preservative, earning him a large bonus check.