A Study Evaluating the Safety and Efficacy of Neoadjuvant and Adjuvant Tiragolumab Plus Atezolizumab, With or Without Platinum-Based Chemotherapy, in Participants With Previously Untreated Locally Advanced Resectable Stage II, IIIA, or Select IIIB Non-Small Cell Lung Cancer

Key inclusion criteria:

* Histologically or cytologically confirmed Stage II, IIIA, or select IIIB (T3N2 only) NSCLC of squamous or non-squamous histology
* Eligible for R0 resection with curative intent at the time of screening
* Adequate pulmonary function to be eligible for surgical resection with curative intent
* Eligible to receive a platinum-based chemotherapy regimen
* Measurable disease, as assessed by the investigator per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1
* Availability of a representative tumor specimen that is suitable for determination of PD-L1 status
* Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1
* Normal life expectancy, excluding lung cancer mortality risk
* Adequate hematologic and end-organ function
* Negative human immunodeficiency virus (HIV) test at screening
* Negative serology for active hepatitis B virus (HBV) and active hepatitis C virus (HCV) at screening

Key Exclusion Criteria:

* NSCLC with histology of large cell neuroendocrine carcinoma, sarcomatoid carcinoma, or NSCLC not otherwise specified
* Small cell lung cancer (SCLC) histology or NSCLC with any component of SCLC
* Any prior therapy for lung cancer
* Active or history of autoimmune disease or immune deficiency
* History of idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced pneumonitis, idiopathic pneumonitis, or evidence of active pneumonitis on screening chest computed tomography (CT) scan
* Active tuberculosis
* Significant cardiovascular disease
* NSCLC with an activating EGFR mutation or ALK fusion oncogene
* Known c-ros oncogene 1 (ROS1) rearrangement
* History of malignancy other than NSCLC within 5 years prior to screening, with the exception of malignancies with negligible risk of metastasis or death
* Severe infection within 4 weeks prior to initiation of study treatment or any active infection that, in the opinion of the investigator, could impact patient safety
* Prior treatment with CD127 agonists or immune checkpoint blockade therapies, including anti-CTLA-4, anti-PD-1, anti-TIGIT, and anti-PD-L1 therapeutic antibodies
* Treatment with systemic immunostimulatory agents
* Treatment with systemic immunosuppressive medication
* Pregnancy or breastfeeding