Inclusion Criteria:

* Adult patients 18 years of age or older with clinically or pathologically defined MM in accordance with International Myeloma Working Group or as stated in office note / clinical assessment from treating physician.

\*All types of active myeloma are eligible including both newly diagnosed and previously treated provided plans are to start a new treatment or restart a prior treatment.
* Healthy Volunteer Subjects: Adult 18 years of age or older with no known hematologic disorder such as anemia, leukemia, etc. who is considered healthy based on assessment by PI. (Cohort 1 only).
* Able to give informed consent.
* Does not have any exclusions related to PET/MR imaging: No implanted medical devices such as: pacemaker, defibrillator, neurostimulator, artificial heart valve, cerebral aneurysm clips, no accidental exposure to metal fragments (if applicable)
* If applicable for administration of contrast with MRI imaging subject must have a calculated GFR of at least 60 mg/mL/1.73 m\^2.
* Not currently pregnant or nursing: Subject must be surgically sterile (has had a documented bilateral oophorectomy and/or documented hysterectomy), post-menopausal (cessation of menses for more than 1 year), non-lactating, or of childbearing potential for whom a urine pregnancy test (with the test performed within the 24 hour period immediately prior to administration of 64Cu-LLP2A) is negative.

Exclusion Criteria:

* Patients with other invasive malignancies, with the exception of non-melanoma skin cancer, who had (or have) any evidence of the other cancer present within the last 5 years.
* Unable to tolerate up to 90 min of PET/MR or PET/CT imaging per imaging session.