diff --git a/app/modules/Smtp/Application/Mail/Attachment.php b/app/modules/Smtp/Application/Mail/Attachment.php
index 61de022..6a0b4f9 100644
--- a/app/modules/Smtp/Application/Mail/Attachment.php
+++ b/app/modules/Smtp/Application/Mail/Attachment.php
@@ -14,6 +14,7 @@ public function __construct(
         private ?string $filename,
         private string $content,
         private string $type,
+        private ?string $contentId,
     ) {
         $this->id = (string) Uuid::uuid4();
     }
@@ -37,4 +38,9 @@ public function getId(): string
     {
         return $this->id;
     }
+
+    public function getContentId(): ?string
+    {
+        return $this->contentId;
+    }
 }
diff --git a/app/modules/Smtp/Application/Mail/Parser.php b/app/modules/Smtp/Application/Mail/Parser.php
index b33473d..b64343f 100644
--- a/app/modules/Smtp/Application/Mail/Parser.php
+++ b/app/modules/Smtp/Application/Mail/Parser.php
@@ -66,6 +66,7 @@ private function buildAttachmentFrom(array $attachments): array
             $part->getFilename(),
             $part->getContent(),
             $part->getContentType(),
+            $part->getContentId(),
         ), $attachments);
     }
 
diff --git a/app/modules/Smtp/Application/Storage/AttachmentStorage.php b/app/modules/Smtp/Application/Storage/AttachmentStorage.php
index 3a8c97f..8642703 100644
--- a/app/modules/Smtp/Application/Storage/AttachmentStorage.php
+++ b/app/modules/Smtp/Application/Storage/AttachmentStorage.php
@@ -18,7 +18,7 @@ public function __construct(
         private AttachmentFactoryInterface $factory,
     ) {}
 
-    public function store(Uuid $eventUuid, array $attachments): void
+    public function store(Uuid $eventUuid, array $attachments): iterable
     {
         foreach ($attachments as $attachment) {
             $file = $this->bucket->write(
@@ -27,15 +27,25 @@ public function store(Uuid $eventUuid, array $attachments): void
             );
 
             $this->attachments->store(
-                $this->factory->create(
+                $a = $this->factory->create(
                     eventUuid: $eventUuid,
                     name: $attachment->getFilename(),
                     path: $file->getPathname(),
                     size: $file->getSize(),
                     mime: $file->getMimeType(),
-                    id: $attachment->getId(),
+                    id: $attachment->getContentId() ?? $attachment->getId(),
                 ),
             );
+
+            if ($attachment->getContentId() === null) {
+                continue;
+            }
+
+            yield $attachment->getContentId() => \sprintf(
+                '/api/smtp/%s/attachments/preview/%s',
+                $eventUuid,
+                $a->getUuid(),
+            );
         }
     }
 
diff --git a/app/modules/Smtp/Domain/AttachmentStorageInterface.php b/app/modules/Smtp/Domain/AttachmentStorageInterface.php
index bf509f5..c841818 100644
--- a/app/modules/Smtp/Domain/AttachmentStorageInterface.php
+++ b/app/modules/Smtp/Domain/AttachmentStorageInterface.php
@@ -11,8 +11,9 @@ interface AttachmentStorageInterface
 {
     /**
      * @param MailAttachment[] $attachments
+     * @return iterable<string, string>
      */
-    public function store(Uuid $eventUuid, array $attachments): void;
+    public function store(Uuid $eventUuid, array $attachments): iterable;
 
     public function deleteByEvent(Uuid $eventUuid): void;
 
diff --git a/app/modules/Smtp/Interfaces/Http/Controllers/Attachments/PreviewAction.php b/app/modules/Smtp/Interfaces/Http/Controllers/Attachments/PreviewAction.php
new file mode 100644
index 0000000..a92c71f
--- /dev/null
+++ b/app/modules/Smtp/Interfaces/Http/Controllers/Attachments/PreviewAction.php
@@ -0,0 +1,88 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Modules\Smtp\Interfaces\Http\Controllers\Attachments;
+
+use App\Application\Commands\FindEventByUuid;
+use App\Application\Commands\FindSmtpAttachmentByUuid;
+use App\Application\Domain\ValueObjects\Uuid;
+use App\Application\HTTP\Response\ErrorResource;
+use Modules\Smtp\Domain\AttachmentStorageInterface;
+use Nyholm\Psr7\Stream;
+use Psr\Http\Message\ResponseInterface;
+use Spiral\Cqrs\QueryBusInterface;
+use Spiral\Http\Exception\ClientException\ForbiddenException;
+use Spiral\Http\ResponseWrapper;
+use Spiral\Router\Annotation\Route;
+use OpenApi\Attributes as OA;
+
+#[OA\Get(
+    path: '/api/smtp/{eventUuid}/attachments/preview/{uuid}',
+    description: 'Preview an attachment by UUID',
+    tags: ['Smtp'],
+    parameters: [
+        new OA\PathParameter(
+            name: 'eventUuid',
+            description: 'Event UUID',
+            required: true,
+            schema: new OA\Schema(type: 'string', format: 'uuid'),
+        ),
+        new OA\PathParameter(
+            name: 'uuid',
+            description: 'Attachment UUID',
+            required: true,
+            schema: new OA\Schema(type: 'string', format: 'uuid'),
+        ),
+    ],
+    responses: [
+        new OA\Response(
+            response: 200,
+            description: 'Success',
+            headers: [
+                new OA\Header(header: 'Content-Type', schema: new OA\Schema(type: 'string', format: 'binary')),
+            ],
+        ),
+        new OA\Response(
+            response: 404,
+            description: 'Not found',
+            content: new OA\JsonContent(
+                ref: ErrorResource::class,
+            ),
+        ),
+        new OA\Response(
+            response: 403,
+            description: 'Access denied.',
+            content: new OA\JsonContent(
+                ref: ErrorResource::class,
+            ),
+        ),
+    ],
+)]
+final readonly class PreviewAction
+{
+    public function __construct(
+        private AttachmentStorageInterface $storage,
+    ) {}
+
+    #[Route(route: 'smtp/<eventUuid>/attachments/preview/<uuid>', name: 'smtp.attachments.preview', group: 'api_guest')]
+    public function __invoke(
+        QueryBusInterface $bus,
+        ResponseWrapper $responseWrapper,
+        Uuid $eventUuid,
+        Uuid $uuid,
+    ): ResponseInterface {
+        $event = $bus->ask(new FindEventByUuid($eventUuid));
+        $attachment = $bus->ask(new FindSmtpAttachmentByUuid($uuid));
+
+        if (!$attachment->getEventUuid()->equals($event->getUuid())) {
+            throw new ForbiddenException('Access denied.');
+        }
+
+        $stream = Stream::create($this->storage->getContent($attachment->getPath()));
+
+        return $responseWrapper->create(200)
+            ->withHeader('Content-Type', $attachment->getMime())
+            ->withBody($stream);
+    }
+}
diff --git a/app/modules/Smtp/Interfaces/TCP/Service.php b/app/modules/Smtp/Interfaces/TCP/Service.php
index beb6c2a..1f9d602 100644
--- a/app/modules/Smtp/Interfaces/TCP/Service.php
+++ b/app/modules/Smtp/Interfaces/TCP/Service.php
@@ -94,7 +94,10 @@ private function dispatchMessage(Message $message, ?string $project = null): voi
         $uuid = Uuid::generate();
         $data = $message->jsonSerialize();
 
-        $this->attachments->store(eventUuid: $uuid, attachments: $message->attachments);
+        // TODO: Refactor this
+        foreach ($this->attachments->store(eventUuid: $uuid, attachments: $message->attachments) as $cid => $url) {
+            $data['html'] = \str_replace("cid:$cid", $url, $data['html']);
+        }
 
         $this->bus->dispatch(
             new HandleReceivedEvent(
diff --git a/tests/Feature/Interfaces/TCP/Smtp/EmailTest.php b/tests/Feature/Interfaces/TCP/Smtp/EmailTest.php
index c70224a..86e2047 100644
--- a/tests/Feature/Interfaces/TCP/Smtp/EmailTest.php
+++ b/tests/Feature/Interfaces/TCP/Smtp/EmailTest.php
@@ -14,6 +14,8 @@
 use Spiral\RoadRunnerBridge\Tcp\Response\CloseConnection;
 use Symfony\Component\Mime\Address;
 use Symfony\Component\Mime\Email;
+use Symfony\Component\Mime\Part\DataPart;
+use Symfony\Component\Mime\Part\File;
 use Tests\Feature\Interfaces\TCP\TCPTestCase;
 
 final class EmailTest extends TCPTestCase
@@ -41,6 +43,21 @@ public function testSendEmail(): void
             uuid: $connectionUuid = Uuid::uuid7(),
         );
 
+        // Assert logo-embeddable is persisted to a database
+        $this->accounts->shouldReceive('store')
+            ->once()
+            ->with(
+                \Mockery::on(function (Attachment $attachment) {
+                    $this->assertSame('logo-embeddable', $attachment->getFilename());
+                    $this->assertSame(1206, $attachment->getSize());
+                    $this->assertSame('image/svg+xml', $attachment->getMime());
+
+                    // Check attachments storage
+                    $this->bucket->assertCreated($attachment->getPath());
+                    return true;
+                }),
+            );
+
         // Assert hello.txt is persisted to a database
         $this->accounts->shouldReceive('store')
             ->once()
@@ -56,8 +73,23 @@ public function testSendEmail(): void
                 }),
             );
 
+        // Assert hello.txt is persisted to a database
+        $this->accounts->shouldReceive('store')
+            ->once()
+            ->with(
+                \Mockery::on(function (Attachment $attachment) {
+                    $this->assertSame('logo.svg', $attachment->getFilename());
+                    $this->assertSame(1206, $attachment->getSize());
+                    $this->assertSame('image/svg+xml', $attachment->getMime());
+
+                    // Check attachments storage
+                    $this->bucket->assertCreated($attachment->getPath());
+                    return true;
+                }),
+            );
+
 
-        // Assert world.txt is persisted to a database
+        // Assert logo.svg is persisted to a database
         $this->accounts->shouldReceive('store')
             ->once()
             ->with(
@@ -142,8 +174,12 @@ private function validateMessage(string $messageId, string $uuid): void
         $this->assertSame([], $parsedMessage->getBccs());
 
         $this->assertSame(
-            'Hello Alice.<br>This is a test message with 5 header fields and 4 lines in the message body.',
-            $parsedMessage->textBody,
+            <<<'HTML'
+<img src="cid:test-cid@buggregator">
+Hello Alice.<br>This is a test message with 5 header fields and 4 lines in the message body.
+HTML
+            ,
+            $parsedMessage->htmlBody,
         );
 
         $this->assertSame('', $parsedMessage->htmlBody);
@@ -213,9 +249,18 @@ public function buildEmail(): Email
             )
             ->addFrom(new Address('no-reply@site.com', 'Bob Example'),)
             ->attachFromPath(path: __DIR__ . '/hello.txt',)
-            ->attachFromPath(path: __DIR__ . '/logo.svg',)
-            ->text(
-                body: 'Hello Alice.<br>This is a test message with 5 header fields and 4 lines in the message body.',
+            ->attachFromPath(path: __DIR__ . '/logo.svg')
+            ->addPart(
+                (new DataPart(new File(__DIR__ . '/logo.svg'), 'logo-embeddable'))->asInline()->setContentId(
+                    'test-cid@buggregator',
+                ),
+            )
+            ->html(
+                body: <<<'TEXT'
+<img src="cid:logo-embeddable">
+Hello Alice.<br>This is a test message with 5 header fields and 4 lines in the message body.
+TEXT
+                ,
             );
     }
 }