diff --git a/src/pages/ExamsPage/components/AttemptList.jsx b/src/pages/ExamsPage/components/AttemptList.jsx
index 395ff2e..8b5ad39 100644
--- a/src/pages/ExamsPage/components/AttemptList.jsx
+++ b/src/pages/ExamsPage/components/AttemptList.jsx
@@ -145,23 +145,26 @@ const AttemptList = ({ attempts }) => {
           },
           {
             Header: formatMessage(messages.examAttemptsTableHeaderStartedAt),
-            Cell: ({ row }) => (formatDate(row.original.started_at, {
+            // The ternary operator here sets the value of the started/completed at datetime to
+            // "-" if the value is null, as otherwise the DataTable will default to the
+            // UNIX epoch (i.e. 1/1/1970) for some reason.
+            Cell: ({ row }) => (row.original.started_at ? formatDate(row.original.started_at, {
               year: 'numeric',
               month: 'numeric',
               day: 'numeric',
               hour: 'numeric',
               minute: 'numeric',
-            })),
+            }) : '-'),
           },
           {
             Header: formatMessage(messages.examAttemptsTableHeaderCompletedAt),
-            Cell: ({ row }) => (formatDate(row.original.completed_at, {
+            Cell: ({ row }) => (row.original.completed_at ? formatDate(row.original.completed_at, {
               year: 'numeric',
               month: 'numeric',
               day: 'numeric',
               hour: 'numeric',
               minute: 'numeric',
-            })),
+            }) : '-'),
           },
           {
             Header: formatMessage(messages.examAttemptsTableHeaderStatus),
diff --git a/src/pages/ExamsPage/components/AttemptList.test.jsx b/src/pages/ExamsPage/components/AttemptList.test.jsx
index 964292b..3a20a58 100644
--- a/src/pages/ExamsPage/components/AttemptList.test.jsx
+++ b/src/pages/ExamsPage/components/AttemptList.test.jsx
@@ -57,6 +57,23 @@ describe('AttemptList', () => {
       }
     });
   });
+  it('attempt null start and end time makes "-" appear in UI', () => {
+    render(<AttemptList attempts={[{
+      exam_name: 'Exam 1',
+      username: 'username1',
+      time_limit: 60,
+      exam_type: 'timed',
+      started_at: null,
+      completed_at: null,
+      status: 'second_review_required',
+      attempt_id: 0,
+      severity: 1.0,
+      submission_reason: 'Submitted by user',
+    }]}
+    />);
+    // Expect a two cells with '-' to be present (index 1 is for the second entry)
+    expect(screen.getAllByText('-')[1]).toBeInTheDocument();
+  });
   it('filtering by status displays the correct entry', () => {
     render(<AttemptList attempts={testUtils.defaultAttemptsData.attemptsList} />);
     // Get the 2nd row of data which has the values of defaultAttemptsData[1]