The Gods' Whisper is a powerful artifact created by the Kree. During a battle against the Asgardians it was lost in the realm of Midgard, and was used by Baron von Strucker to control Hela, the Asgardian God of Death, into fighting for the Nazis. With it, the Nazis fought the Invaders.
After Strucker's and Hela's defeat, it was left on Earth. The three heroes who faced them, Human Torch; Bucky Barnes, and Namor, decided it was too powerful, and broke it in three pieces, which were hidden by each of them.
The Pursuer Corps captured Namor and got the location of one of the pieces, Kree soldiers fought the Winter Soldier and obtained the information of the second piece before he escaped, Tanalth fought the Human Torch and claimed to have recovered the second one as well. Using a special machine, Tanalth recovered the memory of the Human Torch about the location of his fragment of the Whisper, but she was later interrupted by Captain America and the Winter Soldier before she could leave. The final piece was recovered during Tanalth's fight against Captain America and Winter Soldier, and she returned to Hala after being informed of the discovery.