Tammy lives in Crown City and runs a flower shop. She witnesses Celebi flying through the city, an event causing the flowers she waters to burst into bloom. Recognizing Celebi's return after twenty years, she immediately finds her friend Joe to share the news. Both recall Celebi's previous visit two decades earlier and feel relief that the city's restored greenery allowed the mythical Pokémon's return.

When the fabricated crisis involving rampaging legendary Pokémon forces the evacuation of Crown City's old town district, Tammy and Joe take shelter inside her flower shop while others flee. Later, she joins Joe, Karl, and Rowena in an intervention to stop the battle between the real legendary beasts—Raikou, Entei, and Suicune—and Zoroark. Their collective effort helps de-escalate the conflict.