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In order to develop a complete theory of star formation, one essentiallyneeds to know two things: what collapses, and how long it takes. This is thesecond paper in a series, where we query how long a parcel of gas takes tocollapse and the process it undergoes. We embed pseudo-Lagrangian tracerparticles in simulations of collapsing molecular clouds, identify the particlesthat end in dense knots, and then examine the collapse history of the gas. Wefind a nearly universal behavior of cruise-then-collapse. We identify gas themoment before it collapses, $t_{\rm{sing}}$, and examine how it transitions tohigh density. We find that the time to collapse is uniformly distributedbetween $0.25 t_{\rm{ff}}$ and the end of the simulation at $\sim 1t_{\rm{ff}}$, and that the collapse duration is universally short, $\Delta t\sim 0.1 t_{\rm{ff}}$. We find that the collapse of each core happens by aprocess akin to violent relaxation, wherein a fast reordering of the potentialand kinetic energies occurs, in $0.1 t_{\rm{ff}}$, after which a virializedobject remains. We describe the collapse in four stages; collection, hardening,singularity, and mosh. Collection sweeps low density gas into moderate density.Hardening brings kinetic and gravitational energies into quasi-equipartition.Singularity is the free-fall collapse, forming a virialized object in $\sim 0.1t_{\rm{ff}}$. Mosh encompasses tidal dynamics of sub clumps and nearby coresduring the collapse. In this work we focus primarily on isolated clumps. Withthis novel lens we can observe the details of collapse.

Collapsing molecular clouds with tracer particles: Part II, Collapse Histories