Inclusion Criteria:

   - Documented initial diagnosis of multiple myeloma according to international myeloma
   working group (IMWG) diagnostic criteria

   - Part 3: Measurable disease cohort A, cohort B, cohort C, and cohort D: multiple
   myeloma must be measurable by central laboratory assessment

   - Eastern Cooperative Oncology Group (ECOG) performance status score of 0 to 2

   - Women of childbearing potential must have a negative pregnancy test at screening and
   prior to the first dose of study drug using a highly sensitive pregnancy test either
   serum (beta human chorionic gonadotropin [hCG]) or urine

   - Willing and able to adhere to the prohibitions and restrictions specified in this
   protocol

Exclusion Criteria:

   - Part 3 only: Cohort A and Cohort C only: exposed to a CAR-T or T cell redirection
   therapy at any time. Cohort B and Cohort D: T cell redirection therapy within 3 months

   - Toxicities from previous anticancer therapies should have resolved to baseline levels
   or to Grade 1 or less except for alopecia or peripheral neuropathy

   - Received a cumulative dose of corticosteroids equivalent to >= 140 milligram (mg) of
   prednisone within the 14-day period before the first dose of study drug (does not
   include pretreatment medication)

   - Stroke or seizure within 6 months prior to signing the informed consent form (ICF)