A hybrid model for the prompt emission. Upper left: a jet is launched with short time-scale compared to the envelope breakout time, as in Nakar (2015). However, the jet does not have time to become quasi-spherical before breaking out; it undergoes significant deceleration, and possibly a small degree of lateral spreading, but the explosion breaks out primarily in the forward direction, leaving the envelope mostly intact. Thermal emission could be observed, e.g. from the walls of the jet cavity, once material clears out along the line of sight. Upper right: as in our model, the fast SN ejecta heat the remaining envelope, which cools through optical radiation. Lower left: the X-ray afterglow is produced from dust scattering, as described in Section 4.4. Lower right: the radio afterglow comes from a non-relativistic, quasi-spherical blast wave. Because the ejecta are already decelerated to βγ ∼ 1 by the envelope, a spherical flow is more readily achieved than in our jet breakout model.