diff --git a/common/include/filecache.h b/common/include/filecache.h
index 7c85dab..4c2c0e4 100644
--- a/common/include/filecache.h
+++ b/common/include/filecache.h
@@ -5,6 +5,7 @@
 
 #include <QHash>
 #include <QMap>
+#include <QMutex>
 #include <QString>
 #include <physis.hpp>
 
@@ -21,4 +22,5 @@ private:
     QMap<QLatin1String, physis_Buffer> cachedBuffers;
     QHash<QLatin1String, bool> cachedExist;
     GameData& data;
+    QMutex bufferMutex, existMutex;
 };
\ No newline at end of file
diff --git a/common/src/filecache.cpp b/common/src/filecache.cpp
index 6d5b780..2326130 100644
--- a/common/src/filecache.cpp
+++ b/common/src/filecache.cpp
@@ -9,6 +9,8 @@ FileCache::FileCache(GameData& data) : data(data) {}
 
 physis_Buffer &FileCache::lookupFile(const QLatin1String &path)
 {
+    QMutexLocker locker(&bufferMutex);
+
     if (!cachedBuffers.contains(path)) {
         cachedBuffers[path] = physis_gamedata_extract_file(&data, path.data());
     }
@@ -18,6 +20,8 @@ physis_Buffer &FileCache::lookupFile(const QLatin1String &path)
 
 bool FileCache::fileExists(const QLatin1String &path)
 {
+    QMutexLocker locker(&existMutex);
+
     if (!cachedExist.contains(path)) {
         cachedExist[path] = physis_gamedata_exists(&data, path.data());
     }