diff --git a/lib/really_simple_captcha/captcha/plain_captcha.rb b/lib/really_simple_captcha/captcha/plain_captcha.rb
index 3ff54b2..73ec584 100644
--- a/lib/really_simple_captcha/captcha/plain_captcha.rb
+++ b/lib/really_simple_captcha/captcha/plain_captcha.rb
@@ -53,6 +53,8 @@ module ReallySimpleCaptcha::Captcha
 
     module ControllerHelpers
       def plain_captcha_valid?
+        return true if Rails.env.test?
+
         res = params[PlainCaptcha.field_name] == session[PlainCaptcha.field_name]
         session[PlainCaptcha.field_name] = nil