Exoplanetary science has thrived in the last three decades; we now know of thousands of new worlds orbiting other stars, and we are investing new ground-based and space facilities in characterizing them.<br/>However, the interaction between planets and their host stars is still poorly understood. In this new, exciting field, REVErSi will offer a comprehensive theoretical study of star-planet interactions using innovative analytical models and state-of-the-art numerical simulations.<br/>REVErSI will study the tidal, and magnetic interactions of the most common type of exoplanets, Hot Jupiters (HJs), with low-mass stars: M-dwarfs and Solar-like stars. HJs lie close enough to their host star to be magnetically interacting with it. We will study the effect of this interaction on the stellar dynamo, and the magnetic cycle of the star, analytically and numerically. In parallel, we will investigate the role of planet-induced tides on the magnetic activity of the star.<br/>Finally, we will examine the variation of the stellar activity as a means of estimating exoplanetary magnetic fields. This contribution will provide one of the very few currently feasible methods to estimate exoplanetary magnetic fields.