Definition
To suddenly include a strange or illogical event, often leading to radical and often disappointing changes to the narrative of the film.
Origins
From a scene in the film Indiana Jones and the Kingdom of the Crystal Skull (2008), where the main character survives a nuclear detonation by hiding in a lead-lined refrigerator.
See Also
How People Actually Use It
A phrase an Urban Dictionary user tried desperately to implement into circulation by using multiple fake accounts to post barely dissimilar "definitions". This tragic act was committed on May 26th 2008, in reference to the fourth installment of the Indiana Jones franchise.
""While I cannot deny that "Nuke the Fridge" is a witty correlation with the phrase "Jump the Shark", the desperation employed by it's fraudulent author reminisces of making up your own nickname. After 12 years I suppose it's not going to catch on.""
Source: Urban Dictionary