diff --git a/cen64.c b/cen64.c
index 0aa7ec355..a3cef30e3 100644
--- a/cen64.c
+++ b/cen64.c
@@ -53,6 +53,8 @@ int cen64_main(int argc, const char **argv) {
   struct save_file flashram;
   struct is_viewer is, *is_in = NULL;
 
+  FILE* m64_fp = NULL;
+
   if (!cart_db_is_well_formed()) {
     printf("Internal cart detection database is not well-formed.\n");
     return EXIT_FAILURE;
@@ -180,6 +182,30 @@ int cen64_main(int argc, const char **argv) {
     }
   }
 
+  if (options.m64_path) {
+    m64_fp = fopen(options.m64_path, "rb");
+    if (m64_fp != NULL) {
+      // http://tasvideos.org/EmulatorResources/Mupen/M64.html
+      uint8_t header[0x400];
+      size_t n = fread(header, 1, sizeof header, m64_fp);
+      if (n == sizeof header && memcmp(header, "M64\x1A", 4) == 0) {
+        printf("Playing back m64:\n");
+        printf("  ROM name: %.32s (crc %X, region %X)\n",
+               header+0xC4,
+               *(uint32_t*)(header+0xE4),
+               *(uint16_t*)(header+0xE8));
+        printf("  Author: %.222s\n", header+0x222);
+        printf("  Description: %.256s\n", header+0x300);
+      } else {
+        fclose(m64_fp);
+        printf("Invalid Mupen64 movie file '%s'.\n", options.m64_path);
+        return EXIT_FAILURE;
+      }
+    } else {
+      printf("Failed to open Mupen64 movie file '%s'.\n", options.m64_path);
+      return EXIT_FAILURE;
+    }
+  }
 
 
   // Allocate memory for and create the device.
@@ -193,7 +219,7 @@ int cen64_main(int argc, const char **argv) {
 
     if (device_create(device, &ddipl, dd_variant, &ddrom,
       &pifrom, &cart, &eeprom, &sram,
-      &flashram, is_in, controller,
+      &flashram, is_in, controller, m64_fp,
       options.no_audio, options.no_video, options.enable_profiling) == NULL) {
       printf("Failed to create a device.\n");
       status = EXIT_FAILURE;
diff --git a/device/device.c b/device/device.c
index cd5a046c6..4f2289609 100644
--- a/device/device.c
+++ b/device/device.c
@@ -44,7 +44,7 @@ struct cen64_device *device_create(struct cen64_device *device,
   const struct rom_file *pifrom, const struct rom_file *cart,
   const struct save_file *eeprom, const struct save_file *sram,
   const struct save_file *flashram, struct is_viewer *is,
-  const struct controller *controller,
+  const struct controller *controller, FILE* m64_fp,
   bool no_audio, bool no_video, bool profiling) {
 
   // Allocate memory for VR4300
@@ -99,7 +99,7 @@ struct cen64_device *device_create(struct cen64_device *device,
   // Initialize the SI.
   if (si_init(&device->si, &device->bus, pifrom->ptr,
     cart->ptr, dd_variant, eeprom->ptr, eeprom->size,
-    controller)) {
+    controller, m64_fp)) {
     debug("create_device: Failed to initialize the SI.\n");
     return NULL;
   }
@@ -160,6 +160,10 @@ void device_destroy(struct cen64_device *device, const char *cart_path) {
 
     fclose(f);
   }
+
+  if (device->si.m64_fp != NULL) {
+    fclose(device->si.m64_fp);
+  }
 }
 
 // Called when we should (probably?) leave simulation.
@@ -351,4 +355,4 @@ int device_debug_spin(struct cen64_device *device) {
 
 cen64_cold void device_connect_debugger(struct cen64_device *device, void* break_handler_data, vr4300_debug_break_handler break_handler) {
   vr4300_connect_debugger(device->vr4300, break_handler_data, break_handler);
-}
\ No newline at end of file
+}
diff --git a/device/device.h b/device/device.h
index 81709c25a..dd63b3f8e 100644
--- a/device/device.h
+++ b/device/device.h
@@ -61,7 +61,7 @@ cen64_cold struct cen64_device *device_create(struct cen64_device *device,
   const struct rom_file *pifrom, const struct rom_file *cart,
   const struct save_file *eeprom, const struct save_file *sram,
   const struct save_file *flashram, struct is_viewer *is,
-  const struct controller *controller,
+  const struct controller *controller, FILE* m64_fp,
   bool no_audio, bool no_video, bool profiling);
 
 cen64_cold void device_exit(struct bus_controller *bus);
diff --git a/device/options.c b/device/options.c
index 65265061d..014aaa003 100644
--- a/device/options.c
+++ b/device/options.c
@@ -26,6 +26,7 @@ const struct cen64_options default_cen64_options = {
   NULL, // flashram_path
   0,    // is_viewer_present
   NULL, // controller
+  NULL, // m64_path
 #ifdef _WIN32
   false, // console
 #endif
@@ -153,6 +154,15 @@ int parse_options(struct cen64_options *options, int argc, const char *argv[]) {
       options->controller[num] = opt;
     }
 
+    else if (!strcmp(argv[i], "-m64")) {
+      if ((i + 1) >= (argc - 1)) {
+        printf("-m64 requires a path to the movie file.\n\n");
+        return 1;
+      }
+
+      options->m64_path = argv[++i];
+    }
+
     // TODO: Handle this better.
     else
       break;
@@ -282,6 +292,8 @@ void print_command_line_usage(const char *invokation_string) {
       "  -sram <path>               : Path to SRAM save.\n"
       "  -flash <path>              : Path to FlashRAM save.\n"
       "    For mempak see controller options.\n"
+      "Mupen64 movie playback options:\n"
+      "  -m64 <path>                : Path to m64 movie file.\n"
 
     ,invokation_string
   );
diff --git a/device/options.h b/device/options.h
index c8d38b9aa..aca8b8836 100644
--- a/device/options.h
+++ b/device/options.h
@@ -27,6 +27,8 @@ struct cen64_options {
 
   struct controller *controller;
 
+  const char* m64_path;
+
 #ifdef _WIN32
   bool console;
 #endif
diff --git a/si/controller.c b/si/controller.c
index d62330620..f6b9a9660 100644
--- a/si/controller.c
+++ b/si/controller.c
@@ -44,7 +44,8 @@ int si_init(struct si_controller *si, struct bus_controller *bus,
   const uint8_t *pif_rom, const uint8_t *cart_rom,
   const struct dd_variant *dd_variant,
   uint8_t *eeprom, size_t eeprom_size,
-  const struct controller *controller) {
+  const struct controller *controller,
+  FILE* m64_fp) {
   uint32_t cic_seed;
 
   si->bus = bus;
@@ -83,6 +84,9 @@ int si_init(struct si_controller *si, struct bus_controller *bus,
   // controllers
   memcpy(si->controller, controller, sizeof(struct controller) * 4);
 
+  // Mupen64 movie file
+  si->m64_fp = m64_fp;
+
   return 0;
 }
 
@@ -146,7 +150,18 @@ int pif_perform_command(struct si_controller *si,
 
           if (likely(bus->vi->window)) {
             cen64_mutex_lock(&bus->vi->window->event_mutex);
+
+            if (si->m64_fp != NULL) {
+              fread(si->input, 1, 4, si->m64_fp);
+              if (feof(si->m64_fp) || ferror(si->m64_fp)) {
+                fclose(si->m64_fp);
+                si->m64_fp = NULL;
+                printf("Movie playback finished.\n");
+              }
+            }
+            
             memcpy(recv_buf, si->input, sizeof(si->input));
+            
             cen64_mutex_unlock(&bus->vi->window->event_mutex);
           }
 
diff --git a/si/controller.h b/si/controller.h
index 2e8a4ff4b..229ae9807 100644
--- a/si/controller.h
+++ b/si/controller.h
@@ -41,13 +41,16 @@ struct si_controller {
   uint8_t input[4];
   struct eeprom eeprom;
   struct controller controller[4];
+
+  FILE* m64_fp; // Mupen64 movie file
 };
 
 cen64_cold int si_init(struct si_controller *si, struct bus_controller *bus,
   const uint8_t *pif_rom, const uint8_t *cart_rom,
   const struct dd_variant *dd_variant,
   uint8_t *eeprom, size_t eeprom_size,
-  const struct controller *controller);
+  const struct controller *controller,
+  FILE* m64_fp);
 
 int read_pif_rom_and_ram(void *opaque, uint32_t address, uint32_t *word);
 int write_pif_rom_and_ram(void *opaque, uint32_t address, uint32_t word, uint32_t dqm);