Inclusion Criteria:

          -  Has histologically confirmed cutaneous squamous cell carcinoma (cSCC) as the primary
             site of malignancy (metastatic skin involvement from another primary cancer or from an
             unknown primary cancer is not permitted)

          -  Has histologically confirmed LA cSCC with ≥1 high-risk feature(s) as the primary site
             of malignancy

          -  Has undergone complete macroscopic resection of all known cSCC disease with or without
             microscopic positive margins. For those participants with residual microscopic
             positive margin involvement, confirmation that additional re-excision is not possible
             must be provided

          -  Has completed adjuvant radiotherapy (RT) for LA cSCC with last dose of RT ≥4 weeks and
             ≤16 weeks from randomization

          -  Has received an adequate post-op dose of RT (either hypofractionated or conventional)

          -  Is disease free as assessed by the investigator with complete radiographic staging
             assessment ≤28 days from randomization

          -  Is not pregnant or breastfeeding

          -  Is not a woman of childbearing potential (WOCBP)

          -  Has a negative pregnancy test ≤72 hours before the first dose of study intervention

          -  Has provided an archival or newly-obtained tumor tissue sample adequate for Programmed
             Cell Death Ligand 1 (PD-L1) testing as determined by central laboratory testing

          -  Has a life expectancy of >3 months

          -  Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 ≤10 days
             prior to the first dose of study intervention

        Exclusion Criteria:

          -  Has macroscopic residual cSCC after surgery and/or recurrence with active cSCC disease
             before randomization

          -  Has any other histologic type of skin cancer other than invasive cSCC (eg, basal cell
             carcinoma) that has not been definitively treated with surgery or radiation; Bowen's
             disease; Merkel cell carcinoma; or melanoma

          -  Has received prior therapy with an anti-programmed cell death receptor 1(PD-1), anti-
             PD-L1, or anti-programmed cell death receptor ligand 2 (PD-L2) agent or with an agent
             directed to another co-stimulatory or co-inhibitory T-cell receptor (eg, cytotoxic
             T-lymphocyte-associated protein 4 [CTLA-4], OX-40, CD137)

          -  Has received prior systemic anticancer therapy including investigational agents for
             cSCC ≤4 weeks prior to randomization

          -  Has not recovered from all radiation-related toxicities and has not had radiation
             pneumonitis

          -  Has received a live vaccine ≤30 days prior to the first dose of study intervention

          -  Is currently participating in or has participated in a study of an investigational
             agent or has used an investigational device ≤4 weeks prior to the first dose of study
             intervention

          -  Has an active autoimmune disease that has required systemic treatment in past 2 years
             (ie, with use of disease modifying agents, corticosteroids or immunosuppressive drugs)

          -  Has a history of (noninfectious) pneumonitis/interstitial lung disease that required
             steroids or has current pneumonitis/interstitial lung disease

          -  Has an active infection requiring systemic therapy

          -  Has a known history of human immunodeficiency virus (HIV) infection

          -  Has a known history of hepatitis B (defined as hepatitis B surface antigen [HBsAg]
             reactive) or known active hepatitis C virus (HCV; defined as HCV RNA [qualitative] is
             detected) infection

          -  Is pregnant or breastfeeding or expecting to conceive or father children within the
             projected duration of the study, starting with the screening visit through 120 days
             after the last dose of study intervention

          -  Has had an allogeneic tissue/solid organ transplant