diff --git a/package.json b/package.json
index c2a7eb2..e8a37be 100644
--- a/package.json
+++ b/package.json
@@ -36,6 +36,7 @@
     "jimp": "^0.14.0",
     "jsonwebtoken": "^8.5.1",
     "jwks-rsa": "^1.9.0",
+    "lru-cache": "^6.0.0",
     "mysql2": "^2.1.0",
     "node-fetch": "^2.6.0",
     "react": "^17.0.1",
diff --git a/src/app/components/OutfitMovieLayer.js b/src/app/components/OutfitMovieLayer.js
index 0ac06c2..30482ea 100644
--- a/src/app/components/OutfitMovieLayer.js
+++ b/src/app/components/OutfitMovieLayer.js
@@ -1,4 +1,5 @@
 import React from "react";
+import LRU from "lru-cache";
 import { useToast } from "@chakra-ui/react";
 
 import { loadImage, logAndCapture, safeImageUrl } from "../util";
@@ -261,7 +262,16 @@ function loadScriptTag(src) {
   });
 }
 
+const MOVIE_LIBRARY_CACHE = new LRU(10);
+
 export async function loadMovieLibrary(librarySrc) {
+  // First, check the LRU cache. This will enable us to quickly return movie
+  // libraries, without re-loading and re-parsing and re-executing.
+  const cachedLibrary = MOVIE_LIBRARY_CACHE.get(librarySrc);
+  if (cachedLibrary) {
+    return cachedLibrary;
+  }
+
   // These library JS files are interesting in their operation. It seems like
   // the idea is, it pushes an object to a global array, and you need to snap
   // it up and see it at the end of the array! And I don't really see a way to
@@ -322,6 +332,8 @@ export async function loadMovieLibrary(librarySrc) {
     });
   }
 
+  MOVIE_LIBRARY_CACHE.set(librarySrc, library);
+
   return library;
 }
 
diff --git a/src/app/components/OutfitPreview.js b/src/app/components/OutfitPreview.js
index 36db461..b43834d 100644
--- a/src/app/components/OutfitPreview.js
+++ b/src/app/components/OutfitPreview.js
@@ -1,5 +1,6 @@
 import React from "react";
 import { Box, DarkMode, Flex, Text, useColorModeValue } from "@chakra-ui/react";
+import LRU from "lru-cache";
 import { WarningIcon } from "@chakra-ui/icons";
 import { ClassNames } from "@emotion/react";
 import { CSSTransition, TransitionGroup } from "react-transition-group";
@@ -393,29 +394,18 @@ export function usePreloadLayers(layers) {
 
       if (canceled) return;
 
-      let movieClips;
+      let newLayersHaveAnimations;
       try {
-        movieClips = assets
+        newLayersHaveAnimations = assets
           .filter((a) => a.type === "movie")
-          .map((a) => buildMovieClip(a.library, a.libraryUrl));
+          .some(getHasAnimationsForMovieAsset);
       } catch (e) {
-        console.error("Error building movie clips", e);
-        assetPromises.forEach((p) => {
-          if (p.cancel) {
-            p.cancel();
-          }
-        });
+        console.error("Error testing layers for animations", e);
         setError(e);
         return;
       }
 
-      // Some movie clips require you to tick to the first frame of the movie
-      // before the children mount onto the stage. If we detect animations
-      // without doing this, we'll say no, because we see no children!
-      // Example: http://images.neopets.com/cp/items/data/000/000/235/235877_6d273e217c/235877.js
-      movieClips.forEach((mc) => mc.advance());
-
-      setLayersHaveAnimations(movieClips.some(hasAnimations));
+      setLayersHaveAnimations(newLayersHaveAnimations);
       setLoadedLayers(layers);
     };
 
@@ -429,6 +419,34 @@ export function usePreloadLayers(layers) {
   return { loading, error, loadedLayers, layersHaveAnimations };
 }
 
+// This cache is large because it's only storing booleans; mostly just capping
+// it to put *some* upper bound on memory growth.
+const HAS_ANIMATIONS_FOR_MOVIE_ASSET_CACHE = new LRU(50);
+
+function getHasAnimationsForMovieAsset({ library, libraryUrl }) {
+  // This operation can be pretty expensive! We store a cache to only do it
+  // once per layer per session ish, instead of on each outfit change.
+  const cachedHasAnimations = HAS_ANIMATIONS_FOR_MOVIE_ASSET_CACHE.get(
+    libraryUrl
+  );
+  if (cachedHasAnimations) {
+    return cachedHasAnimations;
+  }
+
+  const movieClip = buildMovieClip(library, libraryUrl);
+
+  // Some movie clips require you to tick to the first frame of the movie
+  // before the children mount onto the stage. If we detect animations
+  // without doing this, we'll incorrectly say no, because we see no children!
+  // Example: http://images.neopets.com/cp/items/data/000/000/235/235877_6d273e217c/235877.js
+  movieClip.advance();
+
+  const movieClipHasAnimations = hasAnimations(movieClip);
+
+  HAS_ANIMATIONS_FOR_MOVIE_ASSET_CACHE.set(libraryUrl, movieClipHasAnimations);
+  return movieClipHasAnimations;
+}
+
 /**
  * FadeInOnLoad attaches an `onLoad` handler to its single child, and fades in
  * the container element once it triggers.