We propose a novel approach to describe the $D^+\to K^+K^-K^+$ decay
amplitude, based on chiral effective Lagrangians, which can be used
to extract information about $K\bar{K}$ scattering.
Our trial function is an alternative to the widely used isobar model and
includes both nonresonant three-body interactions and
two-body rescattering amplitudes, based on coupled channels and resonances,
for S- and P-waves with isospin $0$ and $1$.
The latter are unitarized in the $K$-matrix approximation and represent the only
source of complex phases in the problem.
This approach allows one to disentangle the two-body scalar contributions with
different isospins, associated with the $f_0(980)$ and $a_0(980)$ channels.