Inclusion Criteria:

          -  Patients must have one of the histologically advanced solid tumors harboring CCNE1
             amplification: Their diseases are refractory to, or do not have, standard-of-care
             therapy; or they declined standard-of-care therapy; CCNE1 amplification is defined in
             a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory: CCNE1
             amplification > 7 based on targeted custom Ampliseq panel on the Ion Torrent Personal
             Genoma Machine (PGM); or CCNE1 amplification on alternate CLIA platforms such as
             Foundation One, University of Washington (UW)-OncoPlex-Cancer Gene Panel, Memorial
             Sloan Kettering (MSK)-Integrated Mutation Profiling of Actionable Cancer Targets
             (IMPACT), Solid Tumor Genomic Assay (Life Technologies), etc. will also be eligible to
             be treated after principal investigator (PI) approval; patients with known CCNE1
             amplification on local or commercial platforms can start treatment after planned
             biopsy or submission of recent archival sample; central next generation sequencing
             (NGS) CCNE1 and fluorescence in-situ hybridization (FISH) testing will be performed to
             confirm the result

          -  Measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST) version
             1.1

          -  Has read and understands the informed consent form (ICF) and has given written ICF
             prior to any study procedures; patients with impaired decision making capacity (IDMC)
             must have a close caregiver or legally authorized representative (LAR)

          -  Any prior radiation must have been completed at least 7 days prior to the start of
             study drugs, and patients must have recovered from any acute adverse effects prior to
             the start of study treatment

          -  Eastern Cooperative Oncology Group (ECOG) performance status score of 0-1

          -  Absolute neutrophil count (ANC) >= 1500/uL (within 14 days of study drug[s]
             initiation)

          -  Hemoglobin (HgB) >= 9 g/dL for mono-therapy (within 14 days of study drug[s]
             initiation)

          -  Platelets >= 100,000/uL (within 14 days of study drug[s] initiation)

          -  Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) =< 3 x upper limit
             of normal (ULN) or =< 5 x ULN if known hepatic metastases (within 14 days of study
             drug[s] initiation)

          -  Serum bilirubin < ULN or < 1.5 x ULN in patients with liver metastases; or total
             bilirubin < 3.0 x ULN with direct bilirubin within normal limits (WNL) in patients
             with well documented Gilbert's syndrome (within 14 days of study drug[s] initiation)

          -  Serum creatinine =< 1.5 x ULN, or calculated creatinine clearance (CrCl) >= 45 mL/min
             as calculated by the Cockcroft-Gault method or 24-hour measured urine CrCl >= 45
             mL/min (within 14 days of study drug[s] initiation)

          -  Female patients who are not of child-bearing potential and fertile females of
             childbearing potential who agree to use adequate contraceptive measures from 2 weeks
             prior to the study and until 1 month after study treatment discontinuation, who are
             not breastfeeding, and who have a negative serum or urine pregnancy test within 3 days
             prior to the start of study treatment; male patients willing to abstain or use barrier
             contraception (i.e. condoms) for the duration of the study and for 3 months after
             treatment stops

          -  Willingness and ability to comply with study and follow-up procedures

          -  Ability to take oral medications without medical history of malabsorption or other
             chronic gastrointestinal disease, or other conditions that may hamper compliance
             and/or absorption of the study agent

          -  No prior treatment with wee1 kinase inhibition

          -  Provision of an archival tissue block, or 10 formalin-fixed paraffin-embedded (FFPE)
             slides, if available, and if not available having biopsiable disease and agreeing to
             pre-treatment biopsies

        Exclusion Criteria:

          -  Use of anti-cancer treatment drug =< 21 days or 5 half-lives (whichever is shorter)
             prior to the first dose of AZD1775; for drugs for which 5 half-lives is =< 21 days, a
             minimum of 10 days between termination of the prior treatment and administration of
             AZD1775 treatment is required

          -  Previous radiation therapy completed =< 7 days prior to the start of study drugs

          -  Major surgical procedures =< 28 days of beginning AZD1775, or minor surgical
             procedures =< 7 days; no waiting period required following port-a-cath or other
             central venous access placement

          -  Unresolved grade 2 toxicity from prior therapy (except alopecia or anorexia)

          -  Patient has an inability to swallow oral medications; Note: Patient may not have a
             percutaneous endoscopic gastrostomy (PEG) tube or be receiving total parenteral
             nutrition (TPN)

          -  No other anticancer-therapy (chemotherapy, immunotherapy, hormonal anti-cancer
             therapy, radiotherapy [except for palliative local radiotherapy]), biological therapy
             or other novel agent is to be permitted while the patient is receiving study
             medication; patients on luteinizing hormone-releasing hormone (LHRH) analogue
             treatment for more than 6 months are allowed entry into the study and may continue at
             the discretion of the investigator

          -  Known malignant central nervous system (CNS) disease other than neurologically stable,
             treated brain metastases - defined as metastasis having no evidence of progression or
             hemorrhage for at least 2 weeks after treatment; must be off any systemic
             corticosteroids for the treatment of brain metastases for at least 14 days prior to
             enrolment

          -  Patient has had prescription or non-prescription drugs or other products known to be
             sensitive to CYP3A4 substrates or CYP3A4 substrates with a narrow therapeutic index,
             or to be moderate to strong inhibitors/inducers of CYP3A4 which cannot be discontinued
             2 weeks prior to day 1 of dosing and withheld throughout the study until 2 weeks after
             the last dose of study drug; co-administration of aprepitant or fosaprepitant during
             this study is prohibited; the use of sensitive substrates of CYP3A4, such as
             atorvastatin, simvastatin and lovastatin, is also prohibited in this study

          -  Herbal preparations are not allowed throughout the study; these herbal medications
             include but are not limited to: St. John's wort, kava, ephedra (ma hung), gingko
             biloba, dehydroepiandrosterone (DHEA), yohimbe, saw palmetto and ginseng; patients
             should stop using these herbal medications 7 days prior to first dose of study
             treatment

          -  Any known hypersensitivity or contraindication to the components of the study drug
             AZD1775

          -  Any of the following cardiac diseases currently or within the last 6 months as defined
             by New York Heart Association (NYHA) >= class 2

               -  Unstable angina pectoris

               -  Congestive heart failure

               -  Acute myocardial infarction

               -  Conduction abnormality not controlled with pacemaker or medication

               -  Significant ventricular or supraventricular arrhythmias (patients with chronic
                  rate-controlled atrial fibrillation in the absence of other cardiac abnormalities
                  are eligible)

          -  Mean resting corrected QTc interval using the Fridericia formula (QTcF) > 450
             msec/male and > 470 msec/female (as calculated per institutional standards) obtained
             from 3 electrocardiograms (ECGs) 2-5 minutes apart at study entry, or congenital long
             QT syndrome

          -  Pregnant or breastfeeding women

          -  Serious active infection at the time of study entry, or another serious underlying
             medical condition that would impair the ability of the patient to receive study
             treatment

          -  Symptomatic and uncontrolled metastasis in the central nervous system or
             leptomeningeal or lymphangitic carcinomatosis

          -  Presence of other active invasive cancers that do not harbor CCNE1 amplification

          -  Grade 2 or higher peripheral neuropathy

          -  Human immunodeficiency virus requiring highly active antiretroviral therapy (HAART)
             treatment due to unknown drug-drug interactions or has known active hepatitis B (e.g.,
             hepatitis B surface antigen [HBsAg] reactive or C virus [e.g., hepatitis C virus (HCV)
             RNA (quantitative) is detected]) infection