diff --git a/alien.py b/alien.py
new file mode 100644
index 0000000..a6d4f0e
--- /dev/null
+++ b/alien.py
@@ -0,0 +1,22 @@
+import pygame
+from pygame.sprite import Sprite
+
+class Alien(Sprite):
+    """A class to represent a single alien in the fleet"""
+
+    def __init__(self, ai_game):
+        """Init the alien & set it's starting position"""
+        super().__init__()
+        self.screen = ai_game.screen
+        self.screen = ai_game.screen
+
+        # Load the alien image and set it's rect attrib 
+        self.image = pygame.image.load("images/alien.bmp")
+        self.rect = self.image.get_rect()
+
+        # Start each new alien near the top left of screen
+        self.rect.x = self.rect.width
+        self.rect.y = self.rect.height
+
+        # Store the alien's exact horizontal position
+        self.x = float(self.rect.x)
diff --git a/alien_invasion.py b/alien_invasion.py
index 01f88e7..9eba583 100644
--- a/alien_invasion.py
+++ b/alien_invasion.py
@@ -2,6 +2,8 @@
 import pygame
 from settings import Settings
 from ship import Ship
+from bullet import Bullet
+from alien import Alien
 
 
 class AlienInvasion:
@@ -19,6 +21,10 @@ def __init__(self) -> None:
         pygame.display.set_caption("Alien Invasion")
 
         self.ship = Ship(self)
+        self.bullets = pygame.sprite.Group()
+        self.aliens = pygame.sprite.Group()
+
+        self._create_fleet()
 
         # Set the background color.
         self.bg_color = (230, 230, 230)
@@ -28,6 +34,7 @@ def run_game(self):
         while True:
             self._check_events()
             self.ship.update()
+            self._update_bullets()
             self._update_screen()
             self.clock.tick(60)
 
@@ -51,6 +58,8 @@ def _check_keydown_events(self, event):
             self.ship.moving_left = True
         elif event.key == pygame.K_q:
             sys.exit()
+        elif event.key == pygame.K_SPACE:
+            self._fire_bullet()
 
     def _check_keyup_events(self, event):
         """Respond to key releases"""
@@ -59,14 +68,40 @@ def _check_keyup_events(self, event):
         elif event.key == pygame.K_LEFT:
             self.ship.moving_left = False
 
+    def _fire_bullet(self):
+        """Create a new bullet and add it to the bullets group"""
+        if len(self.bullets) < self.settings.bullets_allowed:
+            new_bullet = Bullet(self)
+            self.bullets.add(new_bullet)
+
+    def _update_bullets(self):
+        """Update position of bullets & delete old bullets."""
+        # Update bullet positions.
+        self.bullets.update()
+
+        # Delete bullets at top of screen
+        for bullet in self.bullets.copy():
+            if bullet.rect.bottom <= 0:
+                self.bullets.remove(bullet)
+        # print(len(self.bullets))  
+
+    def _create_fleet(self):
+        """Create the fleet of aliens"""
+        # Make an alien
+        alien = Alien(self)
+        self.aliens.add(alien)
+
+
     def _update_screen(self):
         """Update images on the screen, and flip to the new screen."""
         self.screen.fill(self.settings.bg_color)
+        for bullet in self.bullets.sprites():
+            bullet.draw_bullet()
         self.ship.blitme()
+        self.aliens.draw(self.screen)
 
         pygame.display.flip()
 
-
 if __name__ == "__main__":
     # Make a game instance & run the game.
     ai = AlienInvasion()
diff --git a/bullet.py b/bullet.py
index 70965ce..69335b3 100644
--- a/bullet.py
+++ b/bullet.py
@@ -1,5 +1,5 @@
 import pygame
-from pygame.sprite import _Group, Sprite
+from pygame.sprite import Sprite
 
 class Bullet(Sprite):
     """A class to manage bullets fired from the ship"""
diff --git a/images/alien.bmp b/images/alien.bmp
new file mode 100644
index 0000000..dbe01a0
Binary files /dev/null and b/images/alien.bmp differ
diff --git a/settings.py b/settings.py
index 541560b..bc8f07e 100644
--- a/settings.py
+++ b/settings.py
@@ -16,3 +16,4 @@ def __init__(self) -> None:
         self.bullet_width = 3
         self.bullet_height = 15
         self.bullet_color = (60, 60, 60)
+        self.bullets_allowed = 5