  The appearance of topologically protected states at the surface of an
ordinary insulator is a rare occurrence and to date only a handful of materials
are known for having this property. An intriguing question concerns the
possibility of forming topologically protected interfaces between different
materials. Here we propose that a topological phase can be transferred to
graphene by proximity with the three-dimensional topological insulator
Bi$_2$Se$_3$. By using density functional and transport theory we prove that,
at the verge of the chemical bond formation, a hybrid state forms at the
graphene/Bi$_2$Se$_3$ interface. The state has Dirac-cone-like dispersion at
the $\Gamma$ point and a well-defined helical spin-texture, indicating its
topologically protected nature. This demonstrates that proximity can transfer
the topological phase from Bi$_2$Se$_3$ to graphene.
