Evolution of the BH set on a circular orbit initially of radius r = 1.5kpc (top left to bottom right). The black arrow indicates the velocity vector. Large spiral waves and Jeans fragments develop quickly due to the lower stellar velocity dispersion. The BH binds with stars and opens a gap in its wake, which leads to a steady loss of angular momentum and inward migration. This is most visible in the frames with time running from t = 41 Myr to 915 Myr. At t = 915 Myr the BH sits at r ≈ 20pc with a rest-frame velocity ≃9km s¹. Non-axi-symmetric clumps of stars dislodge the BH which acquires significant angular momentum by dynamical traction in the later stages of evolution (on a timescale ∼500 Myr). Calculations performed with a BH of mass M_• = 1.25 × 10⁷ M_⊙.