Let $F$ be a smooth embedding of the unit circle $\mathbb{S}^{1}$ in $\mathbb{R}^{3}$ such that the image $F(\mathbb{S}^{1})$ is the unknot.
Does there exist a developable surface having $F(\mathbb{S}^{1})$ as boundary?
More formally, can one always find an isometric embedding $G \,\colon V \to \mathbb{R}^{3}$ of some closed subset $V \subset \mathbb{R}^{2}$ such that $G(\partial V) = F(\mathbb{S}^{1})$?