I Dimensions of space (and thought)
1 Entryway passages : demystifying dimensions
2 Restricted passages : rolled-up extra dimensions
3 Exclusive passages : branes, braneworlds, and the bulk
4 Approaches to theoretical physics

II Early twentieth-century advances
5 Relativity : the evolution of Einstein's gravity
6 Quantum mechanics : principled uncertainty, the principal uncertainties, and the uncertainty principle

III The physics of elementary particles
7 The standard model of particle physics : matter's most basic known structure
8 Experimental interlude : verifying the standard model
9 Symmetry : the essential organizing principle
10 The origin of elementary particle masses : spontaneous symmetry breaking and the Higgs mechanism
11 Scaling and grand unification : relating interactions at different lengths and energies
12 The hierarchy problem : the only effective trickle-down theory
13 Supersymmetry : a leap beyond the standard model

IV String theory and branes
14 Allegro (Ma Non Troppo) passage for strings
15 Supporting passages : brane development
16 Bustling passages : braneworlds

V Proposals for extra-dimensional universes
17 Sparsely populated passages : multiverses and sequestering
18 Leaky passages : fingerprints of extra dimensions
19 Voluminous passages : large extra dimensions
20 Warped passage : a solution to the hierarchy problem
21 The warped annotated "Alice"
22 Profound passage : an infinite extra dimension
23 A reflective and expansive passage

VI Closing thoughts
24 Extra dimensions : are you in or out?
25 (In)conclusion