There are some movies (or 'moives') in the gallery you can unlock by doing crap in the game, just like this:

Blue Hunter movie ... Fight the Velociprey in mission "Your First Monster Hunt".

Divine Providence movie ... Encounter the Rathalos in mission "Rathalos Urgent".

King of Heaven movie ... Encounter the Rathalos in mission "One Star Egg Carry".

Lao Shan Lung movie ... Bash the head of Lao Shan Lung (Mt. Lao Dragon).

Menace in the Sand movie ... Make the Cephladrome in mission "Land Shark" barf blood. +1 extinction!

Poison of the Swamp movie ... Squish a Gypceros in the swamp.

Shepard ... Fight the Velocidrome in mission "The Formidable Velocidrome!"\

Supreme Ruler Inferno ... Force the Gravios into exntinction.

Lone Black Wolf movie ... Bash in the Yian Garuga in mission "Slay 20 Velociprey".

Phantom Beast movie ... Fight the Kirin. If you win, you get out.

Ancient Piscine movie ... Fight the Plesioth.

WhiteShadowDarkness ... Finish "Bring me a khezu"