This bill, titled the Nelson Wells Jr. and Dawn Michelle Hunt Unjustly Detained in Communist China Act, aims to enhance diplomatic efforts on behalf of Americans and their family members unjustly detained in the People's Republic of China. It defines "cases of concern" to include United States nationals who may not be officially designated as "wrongfully detained" but for whom credible information suggests they meet certain criteria, as well as family members detained to silence, censor, or intimidate US nationals or influence US government policy. The legislation highlights numerous examples of such detentions, including those involving alleged drug smuggling, exit bans, and retaliation against human rights advocates. The Act mandates the Secretary of State to develop a comprehensive Diplomatic Action Plan within 60 days of enactment. This plan must include designating an official to coordinate diplomatic activities and serve as a family contact, providing guidance for US officials on advocacy efforts, and exploring options for increased diplomatic action, such as expanded use of the International Prison Transfer Program. It also requires a review of international cooperation, available authorities to respond to detentions, and strategies to address the use of "exit bans" targeting US citizens. Furthermore, the Secretary of State must submit a classified report with an unclassified section to Congress within 120 days, detailing the number of detained US nationals, cases of concern, and exit ban cases, along with specific actions taken and strategies for reducing such detentions. The bill also requires the provision of assistance for family members of those deemed cases of concern, including contact information, policy explanations, guidance on engaging diplomatic channels, and information on legal and counseling resources. Upon release, the President is to issue a "declaration of invalidity" for the detention. The legislation establishes a policy to consider those responsible for unjust detentions as having engaged in gross human rights violations, making them sanctionable under the Global Magnitsky Human Rights Accountability Act. It expresses a Sense of Congress that China unjustly detains more Americans than any other country and should be designated as a State Sponsor of Wrongful Detention. Finally, the bill outlines a policy for the United States to use its influence at the United Nations and other multilateral organizations to highlight these cases, condemn exit bans, and press for investigations into retaliatory detentions of family members.