Ah, I see.

So, the animation showed up in a separate window because the label you are using has no parent.
A QWidget without a parent becomes a window by itself.

From your new code I take it you want the animation inside a QGraphicsScene.
For that you need a slightly different approach.

Create your own animation item, by deriving from QObject and QGraphicsPixmapItem.
Let it have a QMovie as a member or provide the QMovie via a setter and store the pointer to it as a member.

In either case make the item show the movie's currentPixmap().

Also connect to the movie's frameChanged() signal to a slot that calls update() on the item.

Cheers,
_