A well packer adapted to be set and reset in a well bore without removal of the packer from the well bore including a packer mandrel adapted to be connected with a tubing string, an interlocking segment assembly on the packer mandrel for releasable connection with the mandrel, a drag spring assembly connected with the interlocking segment assembly for frictional engagement with a well bore wall, a locking slip assembly coupled with the drag spring assembly for locking the packer with the well bore wall, a seal element package assembly connected with slip assembly for sealing around the packer mandrel with the well bore wall, and a detent ring between the slip assembly and the seal element package permitting initial setting of the upper ends of the slips and preloading of the seal element package preliminary to final setting of the slips and expansion of the seal element package.