Devise Authentication unscoped

devise.rb

# config/initializers/devise.rb
#
# We now ask Warden to use :vip_authenticatable when authenticating.
#
# Also, we instruct Warden to load User from session without any default scoping.
#
Devise.setup do |config|
  config.warden do |manager|
    require Rails.root+'lib/vip_authenticable'
    manager.default_strategies(scope: :user).unshift :vip_authenticatable

    manager.serialize_from_session do |keys|
      klass, *args = keys
      user = ActiveSupport::Inflector.constantize(klass).unscoped.serialize_from_session(*args)
    end
  end
end

Another way: http://stackoverflow.com/a/24990576/464685 in case you need that specifically for a single model.