diff --git a/src/lua_baselib.c b/src/lua_baselib.c
index a0c99411b..2a8c62a37 100644
--- a/src/lua_baselib.c
+++ b/src/lua_baselib.c
@@ -28,6 +28,7 @@
 #include "console.h"
 #include "d_netcmd.h" // IsPlayerAdmin
 #include "m_menu.h" // Player Setup menu color stuff
+#include "m_misc.h" // M_MapNumber
 
 #include "lua_script.h"
 #include "lua_libs.h"
@@ -357,6 +358,23 @@ static int lib_pGetColorAfter(lua_State *L)
 	return 1;
 }
 
+// M_MISC
+//////////////
+
+static int lib_mMapNumber(lua_State *L)
+{
+	const char *arg = luaL_checkstring(L, 1);
+	size_t len = strlen(arg);
+	if (len == 2 || len == 5) {
+		char first = arg[len-2];
+		char second = arg[len-1];
+		lua_pushinteger(L, M_MapNumber(first, second));
+	} else {
+		lua_pushinteger(L, 0);
+	}
+	return 1;
+}
+
 // M_RANDOM
 //////////////
 
@@ -3778,6 +3796,9 @@ static luaL_Reg lib[] = {
 	{"M_GetColorAfter",lib_pGetColorAfter},
 	{"M_GetColorBefore",lib_pGetColorBefore},
 
+	// m_misc
+	{"M_MapNumber",lib_mMapNumber},
+
 	// m_random
 	{"P_RandomFixed",lib_pRandomFixed},
 	{"P_RandomByte",lib_pRandomByte},