diff --git a/lib/redlock/client.rb b/lib/redlock/client.rb
index d547f21..46003bd 100644
--- a/lib/redlock/client.rb
+++ b/lib/redlock/client.rb
@@ -30,13 +30,27 @@ def initialize(servers = DEFAULT_REDIS_URLS, options = {})
       @retry_delay = options[:retry_delay] || DEFAULT_RETRY_DELAY
     end
 
+    def testing=(mode)
+      @testing_mode = mode
+    end
+
     # Locks a resource for a given time.
     # Params:
     # +resource+:: the resource (or key) string to be locked.
     # +ttl+:: The time-to-live in ms for the lock.
     # +block+:: an optional block that automatically unlocks the lock.
     def lock(resource, ttl, &block)
-      lock_info = try_lock_instances(resource, ttl)
+      if @testing_mode == :bypass
+        lock_info = {
+          validity: ttl,
+          resource: resource,
+          value: SecureRandom.uuid
+        }
+      elsif @testing_mode == :fail
+        return false
+      else
+        lock_info = try_lock_instances(resource, ttl)
+      end
 
       if block_given?
         begin
@@ -54,6 +68,8 @@ def lock(resource, ttl, &block)
     # Params:
     # +lock_info+:: the lock that has been acquired when you locked the resource.
     def unlock(lock_info)
+      return if @testing_mode == :bypass
+
       @servers.each { |s| s.unlock(lock_info[:resource], lock_info[:value]) }
     end
 
diff --git a/spec/client_spec.rb b/spec/client_spec.rb
index f8d7e05..c0ebd73 100644
--- a/spec/client_spec.rb
+++ b/spec/client_spec.rb
@@ -94,6 +94,30 @@
         end
       end
     end
+
+    context 'when testing with bypass mode' do
+      before { lock_manager.testing = :bypass }
+      after { lock_manager.testing = nil }
+
+      it 'bypasses the redis servers' do
+        expect(lock_manager).to_not receive(:try_lock_instances)
+        lock_manager.lock(resource_key, ttl) do |lock_info|
+          expect(lock_info).to be_lock_info_for(resource_key)
+        end
+      end
+    end
+
+    context 'when testing with fail mode' do
+      before { lock_manager.testing = :fail }
+      after { lock_manager.testing = nil }
+
+      it 'fails' do
+        expect(lock_manager).to_not receive(:try_lock_instances)
+        lock_manager.lock(resource_key, ttl) do |lock_info|
+          expect(lock_info).to eql(false)
+        end
+      end
+    end
   end
 
   describe 'unlock' do