With the discovery of the Higgs boson at the Large Hadron Collider (LHC) at CERN in 2012, the Standard Model (SM) of particle physics reached the triumph of science. Despite its remarkable success in describing the experimental data so far, there exist compelling reasons to expect new physics to extend the SM. One of the strongest evidences for new physics is the existence of Dark Matter. The unprecedented proton-proton collision energy and the large data volumes reached by the LHC, and the CMS detector with supreme particle detection capabilities, provide a unique setting for discovering the particle constituting the dark matter. In several well-motivated extensions to the SM, Axion-Like-Particles (ALPs) are proposed as Dark Matter candidates. Such particles have been the target of several experimental efforts from cosmology to colliders. With AxiTop, the promoters embark on a brand-new analysis to search and discover axion-like dark matter particles in proton-proton collisions at the LHC. For the first time axion particles will be searched for in their production accompanied by top quarks. Since the beginning of the LHC, the promoters of this proposal play leading roles at forefront of various Dark Matter searches, top quark measurements and long-lived particle searches within the CMS experiment, as such they are in the best position to combine the expertise to search for long-lived axion particles in top quark production.