This is a multicenter, cohort, prospective study to evaluate the efficacy and safety of Adebrelimab combined with radiotherapy and chemotherapy as preoperative neoadjuvant therapy for patients with locally advanced rectal cancer. In the study, all subjects who meet the inclusion criteria will enter the short-term radiotherapy queue and the long-term radiotherapy queue at the ratio of 1:1. The short-term radiotherapy queue plans to receive Adebrelimab combined with short-term radiotherapy (5\*5Gy) and Capox chemotherapy as neoadjuvant therapy. The long-term radiotherapy queue plans to receive Adebrelimab combined with long-term radiotherapy (1.8gy × 25-28 times) and capox chemotherapy as neoadjuvant therapy. The TME surgery will be performed 2-3 weeks after the last neoadjuvant therapy is completed. If the surgery cannot be performed within the time window specified in the plan (such as delayed adverse reactions, etc.), the researcher will conduct the surgery according to the patients' requirements.The actual clinical conditions of the subjects were comprehensively considered.