One Froggy Evening is a 1955 six-minute color animated short film written by Michael Maltese and directed by Chuck Jones, it was part of Warner Brothers' Merrie Melodies series of cartoons.

The cartoon has no spoken dialog, relying on visuals, sound effects, and music: mostly songs from the ragtime era, including Hello Ma Baby, and one new song written for the cartoon (The Michigan Rag), in the same style. The singer was uncredited but probably baritone Bill Roberts.

The frog had no name when the cartoon was made, but Chuck Jones later named him Michigan J. Frog after the original song. The character became the mascot of The WB television network in the 1990s.

Steven Spielberg once called One Froggy Evening "the Citizen Kane of animated film" (in the PBS Chuck Jones biography Extremes & Inbetweens: A Life In Animation).

The story may have been inspired by the real-life tale of Old Rip, a horned toad who apparently survived 31 years sealed in the cornerstone of the courthouse in Eastland, Texas. There are also connections to African myths.

Chuck Jones would later reprise Michigan J. Frog in a new cartoon entitled Another Froggy Evening (1998).

In 2003 the United States Library of Congress deemed the film "culturally significant" and selected it for preservation in the National Film Registry.

The film is included on the Looney Tunes Golden Collection Volume 2 DVD (Disc 4), along with an Audio commentary, optional music-only audio track, and a making-of documentary, It Happened One Night.

Story

A construction worker involved in the demolition of a building finds a box inside a cornerstone. He opens it to reveal a singing, dancing frog, complete with top hat and cane. The man tries exploiting the frog's talents, but as it turns out, it won't perform in front of anyone else. In the remainder, the man frantically tries to demonstrate the frog's abilities to the outside world, but all to no avail. After his stay in an asylum, we see the haggard man dejectedly hiding the box in a building that's under construction. Years later, the building is demolished by futuristic ray guns, and the box with the frog is discovered yet again, starting the process all over.