A workover tool string for cutting into a production tubing of a well completion having a top , the well completion comprising a casing into which the production tubing is arranged and a production packer arranged between the casing and the production tubing, defining an annulus above the production packer, the workover tool string comprising: - a longitudinal axis , - a first tool string end and a second tool string end , the first tool string end being arranged closer to the top when submerged into the well completion, - a tubing cutting unit comprising a body , a first unit part , a second unit part and a cutting edge configured to be rotated around the longitudinal axis while being projected in relation to the body for cutting into a wall of the production tubing from within in order to separate a first part of the production tubing closest to the top from a second part of the production tubing, wherein the workover tool string further comprises a tubing penetration unit comprising a projectable penetration element configured to create at least one hole in the wall of the first part for creating fluid communication between the annulus and an inside of the production tubing in order to obtain well control by circulating fluid therebetween, the penetration unit being arranged closer to the first tool string end than the tubing cutting unit, wherein the workover tool string further comprises a deployment tool for setting a plug inside in the second part of the production tubing, the deployment tool being arranged connected to the tubing cutting unit in order that the tubing cutting unit is arranged between the tubing penetration unit and the deployment tool, and the workover tool string comprising a swirl connection between the second unit part of the tubing cutting unit and the deployment tool . - a longitudinal axis , - a first tool string end and a second tool string end , the first tool string end being arranged closer to the top when submerged into the well completion, - a tubing cutting unit comprising a body , a first unit part , a second unit part and a cutting edge configured to be rotated around the longitudinal axis while being projected in relation to the body for cutting into a wall of the production tubing from within in order to separate a first part of the production tubing closest to the top from a second part of the production tubing, wherein the workover tool string further comprises a tubing penetration unit comprising a projectable penetration element configured to create at least one hole in the wall of the first part for creating fluid communication between the annulus and an inside of the production tubing in order to obtain well control by circulating fluid therebetween, the penetration unit being arranged closer to the first tool string end than the tubing cutting unit, wherein the workover tool string further comprises a deployment tool for setting a plug inside in the second part of the production tubing, the deployment tool being arranged connected to the tubing cutting unit in order that the tubing cutting unit is arranged between the tubing penetration unit and the deployment tool, and the workover tool string comprising a swirl connection between the second unit part of the tubing cutting unit and the deployment tool . <EOS>