diff --git a/dotcom-rendering/src/client/adaptiveSite.ts b/dotcom-rendering/src/client/adaptiveSite.ts
index 9162bef68b9..aaab457db01 100644
--- a/dotcom-rendering/src/client/adaptiveSite.ts
+++ b/dotcom-rendering/src/client/adaptiveSite.ts
@@ -1,8 +1,12 @@
+import { log } from '@guardian/libs';
 import { isServer } from '../lib/isServer';
+import { setSchedulerPriorityLastStartTime } from '../lib/scheduler';
 
 /**
  * Whether we should adapt the current page to address poor performance issues.
- * Initially this will only happen as part of a @guardian/open-journalism test.
+ *
+ * It will resolve immediately if `false`, but needs to wait for perf check to
+ * complete if you're in the adaptive site test variant.
  */
 export const shouldAdapt = async (): Promise<boolean> => {
 	if (isServer) return false;
@@ -18,3 +22,19 @@ export const shouldAdapt = async (): Promise<boolean> => {
 
 	return isPerformingPoorly();
 };
+
+/**  Hide all placeholders of non-critical islands */
+const hideAdaptedIslands = () => {
+	const style = document.createElement('style');
+	style.innerHTML = `gu-island:not([priority=critical]) [data-name=placeholder] { display: none; }`;
+	document.head.appendChild(style);
+};
+
+export const adaptSite = (): void => {
+	log('openJournalism', '🎛️ Adapting');
+
+	// disable all tasks except critical ones
+	setSchedulerPriorityLastStartTime('feature', 0);
+	setSchedulerPriorityLastStartTime('enhancement', 0);
+	hideAdaptedIslands();
+};
diff --git a/dotcom-rendering/src/client/index.ts b/dotcom-rendering/src/client/index.ts
index 7d136769f18..701e4b2b4a0 100644
--- a/dotcom-rendering/src/client/index.ts
+++ b/dotcom-rendering/src/client/index.ts
@@ -1,145 +1,152 @@
 import './webpackPublicPath';
+import { adaptSite, shouldAdapt } from './adaptiveSite';
 import { startup } from './startup';
 
-/*************************************************************
- *
- * The following modules are bundled in the entry chunk,
- * so they can be run immediately, but we still want to report
- * on the duration of loading and evaluating them.
- *
- *************************************************************/
+void (async () => {
+	if (await shouldAdapt()) {
+		adaptSite();
+	}
 
-void startup(
-	'bootCmp',
-	() =>
-		import(/* webpackMode: "eager" */ './bootCmp').then(({ bootCmp }) =>
-			bootCmp(),
-		),
-	{
-		priority: 'critical',
-	},
-);
+	/*************************************************************
+	 *
+	 * The following modules are bundled in the entry chunk,
+	 * so they can be run immediately, but we still want to report
+	 * on the duration of loading and evaluating them.
+	 *
+	 *************************************************************/
 
-void startup(
-	'recordInitialPageEvents',
-	() =>
-		import(
-			/* webpackMode: "eager" */ './ophan/recordInitialPageEvents'
-		).then(({ recordInitialPageEvents }) => recordInitialPageEvents()),
-	{
-		priority: 'critical',
-	},
-);
+	void startup(
+		'bootCmp',
+		() =>
+			import(/* webpackMode: "eager" */ './bootCmp').then(({ bootCmp }) =>
+				bootCmp(),
+			),
+		{
+			priority: 'critical',
+		},
+	);
 
-void startup(
-	'ga',
-	() => import(/* webpackMode: "eager" */ './ga').then(({ ga }) => ga()),
-	{
-		priority: 'critical',
-	},
-);
+	void startup(
+		'recordInitialPageEvents',
+		() =>
+			import(
+				/* webpackMode: "eager" */ './ophan/recordInitialPageEvents'
+			).then(({ recordInitialPageEvents }) => recordInitialPageEvents()),
+		{
+			priority: 'critical',
+		},
+	);
 
-void startup(
-	'sentryLoader',
-	() =>
-		import(/* webpackMode: "eager" */ './sentryLoader').then(
-			({ sentryLoader }) => sentryLoader(),
-		),
-	{
-		priority: 'critical',
-	},
-);
+	void startup(
+		'ga',
+		() => import(/* webpackMode: "eager" */ './ga').then(({ ga }) => ga()),
+		{
+			priority: 'critical',
+		},
+	);
 
-void startup(
-	'dynamicImport',
-	() =>
-		import(/* webpackMode: "eager" */ './dynamicImport').then(
-			({ dynamicImport }) => dynamicImport(),
-		),
-	{
-		priority: 'critical',
-	},
-);
+	void startup(
+		'sentryLoader',
+		() =>
+			import(/* webpackMode: "eager" */ './sentryLoader').then(
+				({ sentryLoader }) => sentryLoader(),
+			),
+		{
+			priority: 'critical',
+		},
+	);
 
-void startup(
-	'islands',
-	() =>
-		import(/* webpackMode: "eager" */ './islands').then(({ islands }) =>
-			islands(),
-		),
-	{
-		priority: 'critical',
-	},
-);
+	void startup(
+		'dynamicImport',
+		() =>
+			import(/* webpackMode: "eager" */ './dynamicImport').then(
+				({ dynamicImport }) => dynamicImport(),
+			),
+		{
+			priority: 'critical',
+		},
+	);
 
-void startup(
-	'poorPerformanceMonitoring',
-	() =>
-		import(/* webpackMode: "eager" */ './poorPerformanceMonitoring').then(
-			({ recordPoorPerformance }) => recordPoorPerformance(),
-		),
-	{
-		priority: 'critical',
-	},
-);
+	void startup(
+		'islands',
+		() =>
+			import(/* webpackMode: "eager" */ './islands').then(({ islands }) =>
+				islands(),
+			),
+		{
+			priority: 'critical',
+		},
+	);
 
-/*************************************************************
- *
- * The following modules are lazy loaded,
- * because they are lower priority and do not want to block
- * the modules above on loading these.
- *
- * We are not assigning chunk name to allow Webpack
- * to optimise chunking based on its algorithm.
- *
- *************************************************************/
+	void startup(
+		'poorPerformanceMonitoring',
+		() =>
+			import(
+				/* webpackMode: "eager" */ './poorPerformanceMonitoring'
+			).then(({ recordPoorPerformance }) => recordPoorPerformance()),
+		{
+			priority: 'critical',
+		},
+	);
 
-void startup(
-	'atomIframe',
-	() =>
-		import(
-			/* webpackMode: 'lazy' */
-			'./atomIframe'
-		).then(({ atomIframe }) => atomIframe()),
-	{ priority: 'feature' },
-);
+	/*************************************************************
+	 *
+	 * The following modules are lazy loaded,
+	 * because they are lower priority and do not want to block
+	 * the modules above on loading these.
+	 *
+	 * We are not assigning chunk name to allow Webpack
+	 * to optimise chunking based on its algorithm.
+	 *
+	 *************************************************************/
 
-void startup(
-	'embedIframe',
-	() =>
-		import(
-			/* webpackMode: 'lazy' */
-			'./embedIframe'
-		).then(({ embedIframe }) => embedIframe()),
-	{ priority: 'feature' },
-);
+	void startup(
+		'atomIframe',
+		() =>
+			import(
+				/* webpackMode: 'lazy' */
+				'./atomIframe'
+			).then(({ atomIframe }) => atomIframe()),
+		{ priority: 'feature' },
+	);
 
-void startup(
-	'newsletterEmbedIframe',
-	() =>
-		import(
-			/* webpackMode: 'lazy' */
-			'./newsletterEmbedIframe'
-		).then(({ newsletterEmbedIframe }) => newsletterEmbedIframe()),
-	{ priority: 'feature' },
-);
+	void startup(
+		'embedIframe',
+		() =>
+			import(
+				/* webpackMode: 'lazy' */
+				'./embedIframe'
+			).then(({ embedIframe }) => embedIframe()),
+		{ priority: 'feature' },
+	);
 
-void startup(
-	'relativeTime',
-	() =>
-		import(
-			/* webpackMode: 'lazy' */
-			'./relativeTime'
-		).then(({ relativeTime }) => relativeTime()),
-	{ priority: 'feature' },
-);
+	void startup(
+		'newsletterEmbedIframe',
+		() =>
+			import(
+				/* webpackMode: 'lazy' */
+				'./newsletterEmbedIframe'
+			).then(({ newsletterEmbedIframe }) => newsletterEmbedIframe()),
+		{ priority: 'feature' },
+	);
 
-void startup(
-	'initDiscussion',
-	() =>
-		import(
-			/* webpackMode: 'lazy' */
-			'./discussion'
-		).then(({ discussion }) => discussion()),
-	{ priority: 'feature' },
-);
+	void startup(
+		'relativeTime',
+		() =>
+			import(
+				/* webpackMode: 'lazy' */
+				'./relativeTime'
+			).then(({ relativeTime }) => relativeTime()),
+		{ priority: 'feature' },
+	);
+
+	void startup(
+		'initDiscussion',
+		() =>
+			import(
+				/* webpackMode: 'lazy' */
+				'./discussion'
+			).then(({ discussion }) => discussion()),
+		{ priority: 'feature' },
+	);
+})();