∙ Disease specific inclusion criteria:

• Subjects must have histologically confirmed acute myeloid leukemia that meets any of the following criteria:

‣ Refractory to at least two attempts at prior induction therapy. An attempt is defined as either a single cycle of combination chemotherapy such as daunorubicin/anthracycline OR a single monthly cycle of a hypomethylating agent with venetoclax.

⁃ Patients with FLT3-ITD or -TKD mutations must have received at least one commercially available inhibitor of FLT3.

⁃ Patients with NPM1 mutation or rearrangements of MLL must be refractory to revumenib.

⁃ Patients with mutations in IDH1 or IDH2 must be refractory to at least one commercially available inhibitor of IDH1 or IDH2, respectively.

⁃ Relapsed AML when relapse occurred within 6 months of achieving an initial complete remission.

⁃ Patients must have either failed prior FDA approved agents or, in the opinion of the treating physician, have a sufficiently low probability of response to existing FDA approved agents to warrant treatment on an investigational protocol.

∙ Other inclusion criteria:

• Patients aged 18 through 70 years old are eligible.

• Must have an available, haplotype mismatched related individual that meets criteria for cell donation according to the FACT guidelines.

• Patients must have Karnofsky performance status ≥70%.

• Adequate cardiac function as defined as a systolic LV ejection fraction ≥50% at rest and absence of New York Heart Association stage III or IV congestive heart failure.

• Adequate pulmonary function as defined as a resting SpO2 ≥ 92% on room air at rest.

• Serum bilirubin ≤ 5 mg/dL.

• AST and ALT ≤ 2.5x ULN unless thought to be disease related.

• Estimated or measured creatinine clearance \> 50 mL/min.

• Subjects must be free from all systemic immune suppression for at least 4 weeks prior to the start of intended therapy.

• For women of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraception and agreement to refrain from donating eggs, as defined below: Women must remain abstinent or use contraceptive methods with a failure rate of \<1% per year during the treatment period and for 5 months after the final dose of atezolizumab. Women must refrain from donating eggs during this same period.

• Negative HIV test at screening.

• Negative hepatitis B surface antigen (HBsAg) test at screening OR positive HBsAg is allowed if a negative HBcAb or a negative quantitative hepatitis B virus (HBV) (DNA \< 500 IU/mL) assay are documented.

• Negative hepatitis C virus (HCV) antibody test at screening, or positive HCV antibody test followed by a negative HCV RNA test at screening The HCV RNA test must be performed for patients who have a positive HCV antibody test.

• For patients receiving therapeutic anticoagulation: Stable anticoagulant regimen for 2 weeks prior to enrollment.

• Timing of treatment relative to prior therapies:

‣ Bridging therapy with hydrea is allowed but is required to be tapered off prior to NK infusion.

⁃ Any experimental biological treatments must be discontinued for at least 5 half-lives prior to initiation of study therapy.

⁃ Patients must be \>5 half-lives from receipt of other cytotoxic or targeted therapy.