This legislation addresses the ongoing fentanyl public health crisis by implementing new immigration restrictions. It specifically targets covered aliens , defined as individuals attempting unlawful entry from Canada or Mexico without proper travel documents and who are being held for immigration processing. The bill mandates an immediate suspension of admittance for these covered aliens into the United States. Any such individuals attempting entry while the suspension is active must be rapidly returned to their country of origin or the country from which they entered, with the Secretary of Homeland Security authorized to use repatriation flights. This measure aims to protect public health by reducing the risk of these individuals introducing, selling, trafficking, or otherwise illicitly disseminating deadly fentanyl into the United States.