  We first establish several general properties of modality of algebraic group
actions. In particular, we introduce the notion of a modality-regular action
and prove that every visible action is modality-regular. Then, using these
results, we classify irreducible linear representations of connected simple
algebraic groups of every fixed modality $\leqslant 2$. Next, exploring a finer
geometric structure of linear actions, we generalize to the case of any
cyclically graded semisimple Lie algebra the notion of a packet (or a
Jordan/decomposition class) and establish the properties of packets.
