diff --git a/lib/wraith/save_images.rb b/lib/wraith/save_images.rb
index 151e3c6f..b697be06 100644
--- a/lib/wraith/save_images.rb
+++ b/lib/wraith/save_images.rb
@@ -136,8 +136,8 @@ def capture_image_selenium(screen_sizes, url, file_name, selector, global_before
           driver.manage.window.resize_to(width, height || 1500)
           driver.navigate.to url
           driver.manage.timeouts.implicit_wait = wraith.settle
-          driver.execute_script(File.read(global_before_capture)) if global_before_capture
-          driver.execute_script(File.read(path_before_capture)) if path_before_capture
+          driver.execute_async_script(File.read(global_before_capture)) if global_before_capture
+          driver.execute_async_script(File.read(path_before_capture)) if path_before_capture
           resize_to_fit_page(driver) unless height
           driver.save_screenshot(new_file_name)
           crop_selector(driver, selector, new_file_name) if selector && selector.length > 0
diff --git a/spec/js/global--chrome.js b/spec/js/global--chrome.js
index 63cc23f0..fb1d9f3f 100644
--- a/spec/js/global--chrome.js
+++ b/spec/js/global--chrome.js
@@ -1,4 +1,6 @@
+var callback = arguments[arguments.length-1];
 (function () {
     document.body.innerHTML = " ";
     document.body.style['background-color'] = 'red';
+    callback();
 })();
diff --git a/spec/js/path--chrome.js b/spec/js/path--chrome.js
index 2d3ca011..052217bf 100644
--- a/spec/js/path--chrome.js
+++ b/spec/js/path--chrome.js
@@ -1,4 +1,6 @@
+var callback = arguments[arguments.length-1];
 (function () {
     document.body.innerHTML = " ";
     document.body.style['background-color'] = 'green';
+    callback();
 })();