diff --git a/lib/docker.js b/lib/docker.js
index 89705eb..0f2e078 100644
--- a/lib/docker.js
+++ b/lib/docker.js
@@ -159,7 +159,7 @@ function dockerImagesInspect(imageID, payload) {
     process.nextTick(() => {
       imageID = imageID || '';
       if (typeof imageID !== 'string') {
-        resolve();
+        return resolve();
       }
       const imageIDSanitized = (util.isPrototypePolluted() ? '' : util.sanitizeShellString(imageID, true)).trim();
       if (imageIDSanitized) {