def parse_box_plays(soup):
    """
    Given the soup of the play-by-play page, parse out the score series.

    :soup: BeautifulSoup instance.
    :returns: A list of integers representing the scores after each play.

    """
    # Found by reading the HTML.
    play_div = soup.find_all("div", class_="stats-fullbox")[1]
    play_table = play_div.table

    # First row contains links to sets, which we don't care about.
    rows = play_table.find_all("tr")[1:]
    # All scores are inside of <td></td> tags with the "bold" class. These
    # appear to be the only things in this class here.
    scores = play_table.find_all("td", class_="bold")
    scores = [s.text for s in scores if s.text]

    # Scores are "away-home".
    score_pairs = [s.split("-") for s in scores]

    # Grab the scores we care about: OU.
    # The away name is first, then an empty column, then the home name.
    names = rows[0].find_all("th")
    away = names[0].text
    home = names[-1].text

    ou_index = 0 if away == "OU" else 1
    ou_scores = [int(s[ou_index]) for s in score_pairs]
    return ou_scores