diff --git a/tests/test_cli.py b/tests/test_cli.py
index 5c283171..0e913b5b 100644
--- a/tests/test_cli.py
+++ b/tests/test_cli.py
@@ -222,6 +222,42 @@ def test_start_existing_frame_stopped(runner, watson, mocker):
     assert watson.current["project"] == "b-project"
 
 
+# watson interrupt existing task with new task, restart existing
+
+def test_interrupt_new_frame_added(runner, watson, mocker):
+    # Simulate a start date so that 'at_dt' is older than now().
+    watson.config.set('options', 'stop_on_start', "true")
+    mocker.patch('arrow.arrow.dt_datetime', wraps=datetime)
+    start_dt = datetime(2019, 4, 10, 15, 0, 0, tzinfo=local_tz_info())
+    arrow.arrow.dt_datetime.now.return_value = start_dt
+    result = runner.invoke(
+        cli.start,
+        ['a-project', '--at', "14:10"],
+        obj=watson,
+    )
+
+    result = runner.invoke(
+        cli.interrupt,
+        ['b-project', '--at', "14:15"],
+        obj=watson,
+    )
+    assert result.exit_code == 0, result.stdout
+
+    assert watson._frames._rows[0].project == "a-project"
+    assert watson._frames._rows[0].stop == arrow.get(
+        "2019-04-10T14:15:00+01:00")
+
+    assert watson._frames._rows[1].project == "b-project"
+    assert watson._frames._rows[1].start == arrow.get(
+        "2019-04-10T14:15:00+01:00")
+    assert watson._frames._rows[1].stop == arrow.get(
+        "2019-04-10T15:00:00+01:00")
+
+    assert watson.current["project"] == "a-project"
+    assert watson.current["start"] == arrow.get(
+        "2019-04-10T15:00:00+01:00")
+
+
 # watson restart
 
 @pytest.mark.parametrize('at_dt', VALID_TIMES_DATA)
diff --git a/watson/cli.py b/watson/cli.py
index 377b76b5..4b5704e7 100644
--- a/watson/cli.py
+++ b/watson/cli.py
@@ -279,6 +279,80 @@ def start(ctx, watson, confirm_new_project, confirm_new_tag, args, at_,
     _start(watson, project, tags, start_at=at_, gap=gap_)
 
 
+@cli.command()
+@click.option('--at', 'at_', required=True, type=DateTime,
+              help=('Start frame at this time. Must be in '
+                    '(YYYY-MM-DDT)?HH:MM(:SS)? format.'))
+@click.argument('args', nargs=-1,
+                shell_complete=get_project_or_task_completion)
+@click.option('-c', '--confirm-new-project', is_flag=True, default=False,
+              help="Confirm addition of new project.")
+@click.option('-b', '--confirm-new-tag', is_flag=True, default=False,
+              help="Confirm creation of new tag.")
+@click.pass_obj
+@click.pass_context
+@catch_watson_error
+def interrupt(ctx, watson, confirm_new_project, confirm_new_tag, args, at_):
+    """
+    Insert a project starting at `--at` time and ending `now`.  You can add
+    tags indicating more specifically what you are working on with `+tag`. The
+    currently running task will be started again.
+
+    If there is already a running project and the configuration option
+    `options.stop_on_start` is not set to a true value (`1`, `on`, `true`, or
+    `yes`), this command will abort.
+
+    Example:
+
+    \b
+    $ watson start apollo11 --at 13:37
+    Starting project apollo11 at 13:37
+    $ watson interrupt apollo13 --at 13:39
+    Starting project apollo13 at 13:39
+    Stopping project apollo11, started an hour ago and stopped just now. (id: e9ccd52) # noqa: E501
+    Starting project apollo11 just now.
+    """
+    if not watson.is_started:
+        raise click.ClickException(
+            'No project running, please use watson start'
+        )
+
+    project = ' '.join(
+        itertools.takewhile(lambda s: not s.startswith('+'), args)
+    )
+    if not project:
+        raise click.ClickException("No project given.")
+
+    # Confirm creation of new project if that option is set
+    if (watson.config.getboolean('options', 'confirm_new_project') or
+            confirm_new_project):
+        confirm_project(project, watson.projects)
+
+    # Parse all the tags
+    tags = parse_tags(args)
+
+    # Confirm creation of new tag(s) if that option is set
+    if (watson.config.getboolean('options', 'confirm_new_tag') or
+            confirm_new_tag):
+        confirm_tags(tags, watson.tags)
+
+    if not watson.config.getboolean('options', 'stop_on_start'):
+        raise click.ClickException(
+            style('error', 'config.stop_on_start is set to false,'
+                           ' can not interrupt running project.'),
+        )
+
+    current = watson.current
+    ctx.invoke(stop, at_=at_)
+    watson.frames.add(project, at_, arrow.utcnow(), tags)
+    _start(
+        watson,
+        current["project"],
+        current["tags"],
+        start_at=arrow.utcnow(),
+    )
+
+
 @cli.command(context_settings={'ignore_unknown_options': True})
 @click.option('--at', 'at_', type=DateTime, default=None,
               help=('Stop frame at this time. Must be in '