diff --git a/lib/suo/client/base.rb b/lib/suo/client/base.rb
index 4329138..50a8406 100644
--- a/lib/suo/client/base.rb
+++ b/lib/suo/client/base.rb
@@ -123,7 +123,7 @@ module Suo
         fail NotImplementedError
       end
 
-      def initial_set(key) # rubocop:disable Lint/UnusedMethodArgument
+      def initial_set(key, val = "") # rubocop:disable Lint/UnusedMethodArgument
         fail NotImplementedError
       end
 
@@ -162,7 +162,7 @@ module Suo
         unpacked.map do |time, token|
           [Time.at(time), token]
         end
-      rescue EOFError => _
+      rescue EOFError, MessagePack::MalformedFormatError => _
         []
       end
 
diff --git a/lib/suo/client/memcached.rb b/lib/suo/client/memcached.rb
index a624490..dea8e4a 100644
--- a/lib/suo/client/memcached.rb
+++ b/lib/suo/client/memcached.rb
@@ -20,8 +20,8 @@ module Suo
         @client.set_cas(key, newval, cas)
       end
 
-      def initial_set(key)
-        @client.set(key, "")
+      def initial_set(key, val = "")
+        @client.set(key, val)
       end
     end
   end
diff --git a/lib/suo/client/redis.rb b/lib/suo/client/redis.rb
index ad5d3b8..97d67c3 100644
--- a/lib/suo/client/redis.rb
+++ b/lib/suo/client/redis.rb
@@ -32,8 +32,8 @@ module Suo
         @client.unwatch
       end
 
-      def initial_set(key)
-        @client.set(key, "")
+      def initial_set(key, val = "")
+        @client.set(key, val)
       end
     end
   end
diff --git a/test/client_test.rb b/test/client_test.rb
index 717f182..5ae8b25 100644
--- a/test/client_test.rb
+++ b/test/client_test.rb
@@ -31,6 +31,12 @@ module ClientTests
     assert_equal false, locked
   end
 
+  def test_empty_lock_on_invalid_data
+    @client.send(:initial_set, TEST_KEY, "bad value")
+    locked = @client.locked?(TEST_KEY)
+    assert_equal false, locked
+  end
+
   def test_clear
     lock1 = @client.lock(TEST_KEY, 1)
     refute_nil lock1