'''''Ernest Goes to Jail''''' is a 1990 American comedy film directed by John R. Cherry III and starring Jim Varney. It's the third (technically fourth) film to feature the character ErnestPWorrell.
Ernest is a janitor at the Howard County Bank and Trust only kept at his job out of sympathy. He also looks exactly like death row inmate Felix Nash. During a tour of the prison Nash is kept in after Ernest is called to jury duty, Nash kidnaps Ernest and switches places with him.
Now Nash attempts to assume the life of Ernest P. Worrell while Ernest, confused for Felix Nash, is only days from the electric chair. Can Ernest escape from prison and stop his nefarious doppelganger?
* ActingForTwo: Jim Varney plays both Ernest P. Worrell and Felix Nash.
** CriminalDoppelganger / EvilCounterpart: Naturally, Felix Nash is one for Ernest.
* ArtisticLicenseGunSafety / RecklessGunUsage: When the two security guards show off the new security system, they demonstrate it by shooting at the bulletproof glass, with one of the bank managers standing behind it.
* BigDamnHeroes: After Ernest gets knocked out by Nash during the climax, Bobby suddenly shows up and manages to win a QuickDraw against him. Unfortunately, some police guard dogs proceed to trample him.
* ChekhovsBoomerang: In this movie, Ernest becomes magnetic whenever given an electric shock.
* ChekhovsGun: The various forms of security Chuck and Bobby test out on their boss.
* DisneyDeath: Ernest during the climax. ''Twice''.
* EvilDetectingDog: Rimshot is able to tell Ernest apart from Nash.
* HeelFaceTurn: [[spoiler: Lyle.]]
* HomeMadeinventions: Ernest has a Rube Goldberg-esque way of turning on his TV, he also bathes in a modified washing machine, and dries off using a car-wash grade blow-dryer.
* KnightOfCerebus: Nash is a convicted robber and murderer played straight in an Ernest film.
* NiceHat: Ernest's brown cap. That Felix doesn't wear it when impersonating Ernest is an omen that things aren't what they seem.
** Even though Felix never wore a cap in prison, somehow Ernest ends up with a prison-themed version of his NiceHat when in prison.
* ProperlyParanoid: Bobby is continuously suspicious of Nash while he's posing as Ernest.
* RogueJuror: The single rogue juror was a result of jury tampering. Nash switched places with Ernest and managed to change the verdict.
* RubeGoldbergDevice: Ernest has one in his home, activated by turning on a light switch.
* SelectiveMagnetism: Whenever Ernest is electricuted.
* SlapStick: Whenever Ernest gets shocked, but Nash also gets bumped by the RubeGoldbergDevice frequently.
* SwappedRoles: Between Ernest and Felix Nash.
* TheVoiceless: Lyle. [[spoiler: Until the end, anyway.]]