diff --git a/src/index.ts b/src/index.ts
index 56c233a..d1fd16e 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -122,7 +122,7 @@ function processPatterns(
           split[split.length - 2] = '**';
           split.pop();
         }
-        transformed.push(split.join('/'));
+        transformed.push(split.length ? split.join('/') : '*');
       } else {
         transformed.push(split.length > 1 ? split.slice(0, -1).join('/') : split.join('/'));
       }
diff --git a/test/index.test.ts b/test/index.test.ts
index bd4157c..2fc4fdb 100644
--- a/test/index.test.ts
+++ b/test/index.test.ts
@@ -26,6 +26,12 @@ const cwd = fixture.path;
 
 after(() => fixture.rm());
 
+test('only double star', async () => {
+  const files = await glob({ patterns: ['**'], cwd });
+  assert.deepEqual(files.sort(), ['a/a.txt', 'a/b.txt', 'b/a.txt', 'b/b.txt']);
+});
+
+
 test('directory expansion', async () => {
   const files = await glob({ patterns: ['a'], cwd });
   assert.deepEqual(files.sort(), ['a/a.txt', 'a/b.txt']);