Inclusion Criteria:

          1. Written informed consent and HIPAA authorization for release of personal health
             information prior to registration. NOTE: HIPAA authorization may be included in the
             informed consent or obtained separately. Patients must be willing and able to provide
             written informed consent for this trial.

          2. Age ≥ 18 years at the time of consent.

          3. ECOG Performance Status of 0-1 at screening

          4. Histological or cytological evidence/confirmation per AJCC, 8th edition, of
             hepatocellular carcinoma (HCC).

          5. Measurable disease by RECIST 1.1.

          6. Patients must have a Child-Pugh score of A.

          7. Patients must have at least Barcelona Clinic Liver Cancer (BCLC) stage B HCC and must
             be outside of downstaging criteria (downstaging criteria are defined as: one lesion >
             5 cm and </= 8 cm; two to three lesions each </= 5 cm; four to five lesions </= 3 cm
             with a total tumor diameter of </= 8 cm); six lesions or more regardless of size;
             and/or HCC peripheral vascular involvement of any size or number of tumor (segment
             peripheral, vp1 and vp2 are allowed, but vp3 and vp4 are excluded). NOTE: absence of
             extrahepatic spread, must be confirmed by computed tomography (CT) or magnetic
             resonance imaging (MRI) scan of the chest, abdomen, and pelvis

          8. Archival tissue obtained within 6 months of registration is required. If archival
             tissue is not available, subjects are not eligible.

          9. Patients must not be suitable for or amenable to transplant or resection.

         10. Patients may be treatment naive or have received any number of prior therapies except
             systemic therapy. No prior systemic therapy is permitted. NOTE: Patients who received
             prior local therapy (e.g., radiofrequency ablation, percutaneous ethanol or acetic
             acid injection, cryoablation, high-intensity focused ultrasound) are eligible provided
             the target lesion(s) have not been previously treated with local therapy or the target
             lesion(s) within the field of local therapy have subsequently progressed in accordance
             with RECIST 1.1. Prior TACE IS allowed if FLR is ≥ 40%.

         11. Patients must demonstrate adequate hepatic, bone marrow, and renal function as defined
             in Table below. All screening labs should be performed within 14 days of treatment
             initiation.

               -  Absolute Neutrophil Count (ANC) ≥ 1,500 /μL

               -  Hemoglobin (Hgb) ≥ 9 g/dL without transfusion or EPO dependency (within 7 days of
                  assessment)

               -  Platelet count (Plt) ≥ 50,000 / μL

               -  Serum creatinine OR Measured or calculated CrCl ≤ 1.5 X upper limit of normal
                  (ULN) OR ≥ 60 mL/min for subject with creatinine levels > 1.5 x institutional ULN

               -  Bilirubin ≤ 3.0 X ULN upper limit of normal (ULN)

               -  Aspartate aminotransferase (AST) ≤ 5 X ULN for subjects with cancer in liver

               -  Alanine aminotransferase (ALT) ≤ 5 X ULN for subjects with cancer in liver

               -  Albumin > 2.5 mg/dL

               -  Urine Protein ≤ 2 g

               -  International Normalized Ratio (INR) or Prothrombin Time (PT) or Activated
                  Partial Thromboplastin Time (aPTT) ≤ 1.5 X ULN unless subject is receiving
                  anticoagulant therapy, in which case PT/aPTT must be within therapeutic range for
                  intended use of anticoagulants

         12. Negative HIV test at screening; NOTE: patients with a positive HIV test at screening
             are eligible provided they are stable on anti-retroviral therapy, have a CD4 count >/=
             200/µL, and have an undetectable viral load.

         13. Urine dipstick for proteinuria < 2+ (within 14 days prior to initiation of study
             treatment) Patients discovered to have >/= 2+ proteinuria on dipstick urinalysis at
             baseline should undergo a 24-hour urine collection and must demonstrate <1 g of
             protein in 24 hours.

         14. Documented virology status of hepatitis, as confirmed by screening HBV and HCV
             serology test : For patients with active hepatitis B virus (HBV): HBV DNA < 500 IU/mL
             obtained within 28 days prior to initiation of study treatment, and Anti-HBV treatment
             (per local standard of care; e.g., entecavir) for a minimum of 14 days prior to study
             entry and willingness to continue treatment for the length of the study.

         15. Co-infection of HBV and HCV is an exclusion. Patients with a history of HCV infection
             but who are negative for HCV RNA by PCR will be considered non-infected with HCV.

         16. Prior cancer treatment must be completed at least six months prior to registration and
             the subject must have recovered from all reversible acute toxic effects of the regimen
             (other than alopecia) to Grade ≤ 1 or baseline.

         17. Females of childbearing potential must have a negative serum pregnancy test within 14
             days prior to registration. NOTE: Females are considered of child bearing potential
             unless they are surgically sterile (have undergone a hysterectomy, bilateral tubal
             ligation, or bilateral oophorectomy) or they are naturally postmenopausal for at least
             12 consecutive months.

         18. Females of childbearing potential must be willing to abstain from heterosexual
             activity or to use 2 forms of effective methods of contraception from the time of
             informed consent until 150 days after treatment discontinuation (Arm B). Males of
             childbearing potential must be willing to abstain from heterosexual activity or to use
             2 forms of effective methods of contraception from the time of informed consent until
             210 days after treatment discontinuation (Arm B). The timeframe for female and male
             subjects that randomize to Arm A is from the time of informed consent until 60 days
             after treatment discontinuation.

         19. As determined by the enrolling physician or protocol designee, ability of the subject
             to understand and comply with study procedures for the entire length of the study.

        Exclusion Criteria

          1. Have signs of liver failure, e.g. clinically significant ascites, encephalopathy, or
             variceal bleeding within six months from enrollment.

          2. Prior bleeding event due to esophageal and/or gastric varices within 6 months prior to
             initiation of study treatment. NOTE: Patients must undergo an
             esophagogastroduodenoscopy (EGD), and all size of varices (small to large) must be
             assessed and treated per local standard of care prior to enrollment. Patients who have
             undergone an EGD within 6 months of prior to initiation of study treatment do not need
             to repeat the procedure.

          3. Untreated or incompletely treated esophageal and/or gastric varices with bleeding or
             high-risk for bleeding.

          4. Have evidence of excessive hepatopulmonary shunting (> 20% in 99mTc macro-aggregated
             albumin scan) or angiographically demonstrable and non-occludable gastrointestinal
             shunting, precluding from Y-90 treatment).

          5. Prior history of TACE or transarterial treatment via hepatic artery.

          6. Subject not a TARE candidate, as defined by a lung dose threshold for Y-90 of 30Gy and
             an estimated (future liver remnants) FLR of < 40% at the time of forming the
             comprehensive treatment plan.

          7. Inadequately controlled arterial hypertension (defined as systolic blood pressure (BP)
             ≥150 mmHg and/or diastolic blood pressure > 100 mmHg), based on an average of ≥ 3 BP
             readings on ≥ 2 sessions. NOTE: Anti-hypertensive therapy to achieve these parameters
             is allowable.

          8. Prior history of hypertensive crisis or hypertensive encephalopathy.

          9. Significant cardiovascular disease (such as New York Heart Association Class II or
             greater cardiac disease, myocardial infarction, or cerebrovascular accident) within 3
             months prior to initiation of study treatment, unstable arrhythmia, or unstable
             angina.

         10. Known fibrolamellar HCC, sarcomatoid HCC, or mixed cholangiocarcinoma and HCC.

         11. Major surgery within 4 weeks prior to registration or anticipation of a major surgical
             procedure during study.

         12. Have had prior transplant of any kind.

         13. Have active autoimmune disease that has required systemic treatment in the past 2
             years (i.e. with use of disease modifying agents, corticosteroids, or
             immunosuppressive drugs). Replacement therapy (e.g., thyroxine, insulin, or
             physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency,
             etc.) is not considered a form of systemic treatment. Have history of idiopathic
             pulmonary fibrosis (including bronchiolitis obliterans with organizing pneumonia) or
             evidence of active pneumonitis on screening chest CT scan.

         14. Have untreated central nervous system (CNS) metastatic disease (including spinal cord
             and leptomeningeal disease). NOTE: Subjects with previously treated CNS metastases
             that are radiographically and neurologically stable for at least 6 weeks and do not
             require corticosteroids (of any dose) for symptomatic management are permitted to
             enroll.

         15. Have unresolved toxicities from prior anticancer therapy, defined as having not
             resolved to National Cancer Institute (NCI) CTCAE v5 grade 0 or 1 with the exception
             of alopecia and laboratory values listed per the inclusion criteria. NOTE: Subjects
             with irreversible toxicity that is not reasonably expected to be exacerbated by any of
             the investigational products may be included (e.g., hearing loss) after consultation
             with the sponsor-investigator.

         16. Diagnosed or treated for malignancy other than HCC, unless they meet one of the
             following exceptions:

               -  Malignancy treated with curative intent and with no known active disease present
                  for ≥ 2 years before registration and felt to be at low risk for recurrence by
                  the treating physician.

               -  Adequately treated non-melanoma skin cancer or lentigo maligna without evidence
                  of disease.

               -  Adequately treated cervical carcinoma in situ without evidence of disease.

         17. Have a known or suspected allergy to bevacizumab or atezolizumab or known
             hypersensitivity to Chinese hamster ovary cell products or to any component of the
             atezolizumab or bevacizumab formulation.

         18. Significant vascular disease (e.g., aortic aneurysm requiring surgical repair or
             recent peripheral arterial thrombosis) within 6 months prior to initiation of study
             treatment.

         19. History of hemoptysis (≥ 2.5 mL of bright red blood per episode) within 1 month prior
             to initiation of study treatment.

         20. Evidence of bleeding diathesis or significant coagulopathy (in the absence of
             therapeutic anticoagulation).

         21. Current or recent (within 10 days of first dose of study treatment) use of aspirin (≥
             325 mg/day) or treatment with dipyramidole, ticlopidine, clopidogrel, and cilostazol.

         22. Current or recent (within 10 days prior to study treatment start) use of full-dose
             oral or parenteral anticoagulants or thrombolytic agents for therapeutic (as opposed
             to prophylactic) purpose. NOTE: Prophylactic anticoagulation for the patency of venous
             access devices is allowed provided the activity of the agent results in an INR < 1.5 x
             ULN and aPTT is within normal limits within 14 days prior to initiation of study
             treatment.

         23. Have an uncontrolled intercurrent illness including, but not limited to any of the
             following:

               -  Psychiatric illness/social situations that would limit compliance with study
                  requirements

               -  Have any other disease, metabolic dysfunction, physical examination finding, or
                  clinical laboratory finding giving reasonable suspicion of a disease or condition
                  that contraindicates the use of an investigational drug or that may affect the
                  interpretation of the results or render the patient at high risk from treatment
                  complications.

               -  Active alcohol use, drug use, or a psychiatric disease that would, in the opinion
                  of the sponsor-investigator or a sub-investigator (sub-I), prevent the subject
                  from complying with the study protocol and/or endanger the subject during their
                  participation in the study.

         24. Severe infection within 4 weeks prior to initiation of study treatment, including, but
             not limited to, hospitalization for complications of infection, bacteremia, or severe
             pneumonia. NOTE: Treatment with therapeutic oral or IV antibiotics within 2 weeks
             prior to initiation of study treatment Patients receiving prophylactic antibiotics
             (e.g., to prevent a urinary tract infection or chronic obstructive pulmonary disease
             exacerbation) are eligible for the study.

         25. Pregnant or breastfeeding (NOTE: breast milk cannot be stored for future use while the
             mother is being treated on study).

         26. ave received a live vaccine within 30 days of the planned start of study therapy.
             NOTE: Seasonal influenza vaccines for injection are generally inactivated flu vaccines
             and are allowed; however, intranasal influenza vaccines (e.g., Flu-Mist®) are live
             attenuated vaccines, and are not allowed.

         27. Have received or are receiving any investigational therapy within 28 days prior to the
             first dose of bevacizumab and atezolizumab. NOTE: Subjects may be enrolled in an
             observational (non-interventional) clinical study or in the follow-up period of an
             interventional study.