Instant Convertible

In chase scenes, there comes a time when the trailer of a Mack blocks the driver's path. And, there isn't time to avoid a collision. What does one do?

Answer: DUCK.

If the car is low enough and/or the trailer high enough, most of the car will pass under it safely. Except the roof and windows. The car is perfectly drivable afterward. The driver may even remark, "I've always wanted a convertible." Hence, the name of the trope.

The MythBusters show this trope is Truth in Television: their tow cable-guided test car kept going until it left the test site and crashed into a ravine.

Examples of Instant Convertible include:

Anime & Manga

In Soul Eater Giriko complains the limousine Arachne's Butler arranged to pick them up with after she was resurrected was too cramped and invoked this trope while it was still stationary. Being an Ax Crazy guy with the ability to turn into a chainsaw does that.
In Durarara!!, Shizuo pulls this off on Horada's car by slicing the top off with a highway sign.

Films -- Live Action

James Bond
- 007 shears the top off a doubledecker bus by going under a low bridge in Live and Let Die.
- This is one of many mishaps that happens to Bond's Renault in A View to a Kill.
The long chase scene in The Seven Ups ends with one of these. Only the front half of Roy Scheider's car gets sliced off, though.
In The Toxic Avenger Part 2, during the final chase scene Toxi's cab driver is unable to avoid this fate. After a moment of silence, everyone in the cab freaks out and when the driver starts ranting about how his cab's been ruined, Toxi tells him to chill out 'cause he now has a convertible and hands him a pair of sunglasses (and he does!). Oddly enough, the little Jesus statue in the back is unharmed.
In The Mummy Returns they do this to the second floor of a double decker bus.
Happens to a police car in the live-action Disney comedy No Deposit, No Return.
Terminator
- Terminator 2: When the T-1000, driving a semi, crashes into a demolished bridge, destroying the roof of the truck, the T-1000, being made of liquid metal, is able to reconstruct itself and continue the chase.
  - Reconstruct? It ducked.
    - Both. The T-1000 morphed down into the cab to dodge the impact; the actor leaned over to dodge the expense of another costly special effect.
- Terminator 3 does this with a hearse, badly damaging the terminator trying to cut though the roof in the process.
Averted in A Clockwork Orange. They're already in a convertible, and it suffers no damage whatsoever when it goes under a truck.
In Smokey and the Bandit, Sheriff Buford T. Justice has this happen to him when he can't avoid a truck carrying a concrete I-beam. He continues to drive the roofless police cruiser at high speed across several states for the rest of the movie.

Live Action TV

This happens in the final episode of Perfect Strangers.
It happens to Rosco's cruiser in an episode of The Dukes of Hazzard.
It happens in Top Gear with a Citroen sedan driven by The Stig as part of a test on vehicle height in sports cars (it failed.)
Mr. Lahey's car in Trailer Park Boys.
Averted in the Bugs episode All Under Control. The villain attempts to drive under a truck, only for the car to come to a complete stop.

Western Animation

Happened in an episode of Megas XLR when Coop was taking a driving test at the DMV.
Slight variation in an episode of Garfield and Friends when Jon drives under a billboard and Garfield makes the comment.
Variation in the '90s X-Men animated series, when Cyclops pisses off Wolverine.

Wolverine: Tell Cyclops I made him a convertible.

In one episode of Extreme Ghostbusters, the gang is being chased by the metal-eating Jersey Devil, who blasts the roof of Roland's car. Eduardo then makes the comment.
In the American Dad episode "Dungeons and Wagons", when Stan, Francine, and Roger are fleeing the street racing kidnappers, Roger dumps everything to reduce the car's weight leading to one of the kidnappers driving under the tanker truck and becoming a convertible.
Happens to Cruella Devil's car at the end of One Hundred and One Dalmatians, while she is chasing the moving van the titular dogs were travelling in.
- Her car was already a convertible, though the top was up at the time.

Real Life

The Double-Decker Bus vs Low Bridge variant happens frequently in Britain.