The Teenage Mutant Ninja Turtles are back. (ILM/Paramount Pictures)

The Teenage Mutant Ninja Turtles come ninja turtle-ing back onto the big screen Friday. Leonardo, Donatello, Michelangelo and Raphael are cool, thanks to the fact that they are reptiles and literally cold-blooded. Just like these slippery stars.

Many many many snakes
Much of Indiana Jones’ appeal is that he’s a regular guy — well, one who’s awesome with a whip. He even gets scared, like in 1981’s “Raiders of the Lost Ark” when he gets plunged into a pit with so many snakes we can’t even think about it anymore because snakes.

A Western that just happens to be animated and just happens to star a chameleon, 2011’s “Rango” is a study in genre, allusion and Johnny Depp’s pretty voice.

Ducky et al
Scientists now think dinosaurs may have been neither warm- nor cold-blooded, but somewhere in the middle. But anyone who was a kid in 1988 and saw “The Land Before Time” can certainly say that the plucky group of orphaned dinosaurs at the center of the film were very cool.

The Anaconda
Making snakes more terrifying is easy — just make them bigger and faster and capable of eating Jon Voight, like in 1997’s “Anaconda.”

The sibilant villain from 1967’s “The Jungle Book” had one neat power we should pray snakes never actually figure out: He could hypnotize people before killing them. Actually, that would have been better for Jon Voight.

Read more of Kristen Page-Kirby’s Film Riffs:

‘Dawn of the Planet of the Apes’ is full of killer animals, just like these five films

Melissa McCarthy hits the highway in ‘Tammy,’ Hollywood’s latest road trip

Five movies that aren’t ‘Jersey Boys’ about real musicians